UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

                                    Form 13F

                              FORM 13F COVER PAGE

Report for the Calendar Year or Quarter Ended:         December 31, 2011

Check here if Amendment [   ]; Amendment Number:
This Amendment (Check only one):  [    ]  is a restatement.
                                  [    ]  adds new holdings entries.

Institutional Investment Manager Filing this Report:

Name:     Hennessy Advisors, Inc.
Address:  7250 Redwood Boulevard, Suite 200
          Novato, CA  94945

Form 13F File Number:  028-06715

The institutional investment manager filing this report and the person by whom
it is signed hereby represent that the person signing the report is authorized
to submit it, that all information contained herein is true, correct and
complete, and that it is understood that all required items, statements,
schedules, lists, and tables, are considered integral parts of this form.

Person Signing this Report on Behalf of Reporting Manager:

Name:    Teresa M. Nilsen
Title:   Executive Vice President and Chief Financial Officer
Phone:   (415) 899-1555

Signature, Place, and Date of Signing:

/s/ Teresa M. Nilsen              Novato, CA                   January 31, 2012
--------------------------------------------------------------------------------
Teresa M. Nilsen                  City, State                        Date

Report Type  (Check only one):

[X]   13F HOLDINGS REPORT.  (Check here if all holdings of this reporting
      manager are reported in this report.)

[   ] 13F NOTICE.  (Check here if no holdings reported are in this report,
      and all holdings are reported by other reporting manager(s).)

[   ] 13F COMBINATION REPORT.  (Check here if a portion of the holdings for
      this reporting manager are reported in this report and a portion are
      reported by other reporting manager(s).)


                             FORM 13F SUMMARY PAGE


Report Summary:


Number of Other Included Managers:                  0
                                         ---------------
Form 13F Information Table Entry Total:           218
                                         ---------------
Form 13F Information Table Value Total:      $567,829
                                         ---------------
                                           (thousands)



List of Other Included Managers:     NONE



                                                        FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                           Value   Shares/  Sh/ Put/ Invstmt    Other          Voting Authority
        Name of Issuer         Title of Class     CUSIP   (x1000)  Prn Amt  Prn Call Dscretn   Managers     Sole    Shared   None
------------------------------ ---------------- --------- -------- -------- --- ---- ------- ------------ -------- -------- -------
                                                                                                 
AAR CORP                      COM               000361105     353    18,400  SH      SOLE                  18,400
AARONS INC                    COM PAR $0.50     002535300     542    20,300  SH      SOLE                  20,300
ABBOTT LABORATORIES           COM               002824100   2,553    45,400  SH      SOLE                  45,400
ADVANCE AUTO PARTS INC        COM               00751Y106   1,622    23,300  SH      SOLE                  23,300
AETNA INC NEW                 COM               00817Y108   1,586    37,600  SH      SOLE                  37,600
AIR TRANSPORT SERVICES GRP    COM               00922R105   1,989   421,500  SH      SOLE                 421,500
ALLIANT ENERGY CORP           COM               018802108   5,112   115,900  SH      SOLE                 115,900
ALTRA HOLDINGS INC            COM               02208R106     419    22,250  SH      SOLE                  22,250
ALTRIA GROUP INC              COM               02209S103   2,624    88,500  SH      SOLE                  88,500
AMC NETWORKS INC              CL A              00164V103     429    11,425  SH      SOLE                  11,425
AMERCO                        COM               023586100   2,846    32,200  SH      SOLE                  32,200
AMERIGROUP CORP               COM               03073T102     455     7,700  SH      SOLE                   7,700
AMTRUST FINANCIAL SERVICES    COM               032359309     563    23,700  SH      SOLE                  23,700
ANN INC                       COM               035623107   3,112   125,600  SH      SOLE                 125,600
APOLLO GROUP INC              CL A              037604105   2,069    38,400  SH      SOLE                  38,400
APPLIED MATLS INC             COM               038222105   1,153   107,700  SH      SOLE                 107,700
ASHFORD HOSPITALITY TR INC    COM SHS           044103109   2,642   330,200  SH      SOLE                 330,200
AT&T INC                      COM               00206R102   7,330   242,400  SH      SOLE                 242,400
ATLAS ENERGY LP               COM UNITS LP      04930A104   5,528   227,500  SH      SOLE                 227,500
ATLAS PIPELINE PARTNERS LP    UNIT L P INT      049392103   5,034   135,500  SH      SOLE                 135,500
AUTOLIV INC                   COM               052800109   1,113    20,800  SH      SOLE                  20,800
AUTOMATIC DATA PROCESSING     COM               053015103   2,598    48,100  SH      SOLE                  48,100
AUTONATION INC                COM               05329W102     527    14,300  SH      SOLE                  14,300
AXCELIS TECHNOLOGIES INC      COM               054540109      16    12,400  SH      SOLE                  12,400
BCE INC                       COM NEW           05534B760   2,775    66,600  SH      SOLE                  66,600
BEST BUY CO INC               COM               086516101   1,234    52,800  SH      SOLE                  52,800
BOEING CO                     COM               097023105   1,489    20,300  SH      SOLE                  20,300
BORGWARNER INC                COM               099724106   3,206    50,300  SH      SOLE                  50,300
BRISTOL MYERS SQUIBB CO       COM               110122108   2,925    83,000  SH      SOLE                  83,000
BUCKEYE TECHNOLOGIES INC      COM               118255108   5,360   160,300  SH      SOLE                 160,300
CABELAS INC                   COM               126804301     521    20,500  SH      SOLE                  20,500
CABLEVISION SYS CORP          CL A NY CABLVS    12686C109     486    34,200  SH      SOLE                  34,200
CAMPBELL SOUP CO              COM               134429109   3,680   110,700  SH      SOLE                 110,700
CASCADE CORP                  COM               147195101     495    10,500  SH      SOLE                  10,500
CASEYS GEN STORES INC         COM               147528103   5,203   101,000  SH      SOLE                 101,000
CASH AMER INTL INC            COM               14754D100     459     9,850  SH      SOLE                   9,850
CBS CORP                      CL B              124857202     550    20,250  SH      SOLE                  20,250
CENTERPOINT ENERGY INC        COM               15189T107   4,570   227,500  SH      SOLE                 227,500
CENTURYLINK INC               COM               156700106   1,920    51,600  SH      SOLE                  51,600
CHEVRON CORP NEW              COM               166764100   7,198    67,650  SH      SOLE                  67,650
CHICOS FAS INC                COM               168615102     401    36,000  SH      SOLE                  36,000
CHINA MOBILE LIMITED          SPONSORED ADR     16941M109   2,066    42,600  SH      SOLE                  42,600
CIGNA CORPORATION             COM               125509109   1,415    33,700  SH      SOLE                  33,700
CIMAREX ENERGY CO             COM               171798101   1,071    17,300  SH      SOLE                  17,300
CLIFFS NATURAL RESOURCES INC  COM               18683K101   1,166    18,700  SH      SOLE                  18,700
CMS ENERGY CORP               COM               125896100   5,067   229,500  SH      SOLE                 229,500
COMMERCIAL VEHICLE GROUP      COM               202608105   1,736   192,000  SH      SOLE                 192,000
COMP SIDERURGICA NAC          SPONSORED ADR     20440W105   1,052   128,600  SH      SOLE                 128,600
CONAGRA FOODS INC             COM               205887102   2,669   101,100  SH      SOLE                 101,100
CONOCOPHILLIPS                COM               20825C104   2,565    35,200  SH      SOLE                  35,200
CORN PRODUCTS INTL INC        COM               219023108     526    10,000  SH      SOLE                  10,000
COST PLUS INC                 COM               221485105   3,188   327,000  SH      SOLE                 327,000
COVENTRY HEALTH CARE INC      COM               222862104     463    15,250  SH      SOLE                  15,250
CPI CORP                      COM               125902106     213   117,800  SH      SOLE                 117,800
CROSSTEX ENERGY INC           COM               22765Y104     549    43,400  SH      SOLE                  43,400
CVR ENERGY INC                COM               12662P108     399    21,300  SH      SOLE                  21,300
DDI CORP                      COM 0.0001 NEW    233162502   2,726   292,150  SH      SOLE                 292,150
DELL INC                      COM               24702R101   1,404    96,000  SH      SOLE                  96,000
DFC GLOBAL CORP               COM               23324T107     461    25,550  SH      SOLE                  25,550
DIAGEO P L C                  SPON ADR NEW      25243Q205   2,561    29,300  SH      SOLE                  29,300
DIAMOND OFFSHORE DRILLING     COM               25271C102   1,271    23,000  SH      SOLE                  23,000
DILLARDS INC                  CL A              254067101   4,555   101,500  SH      SOLE                 101,500
DINEEQUITY INC                COM               254423106   2,558    60,600  SH      SOLE                  60,600
DIRECTV                       COM CL A          25490A101   1,385    32,400  SH      SOLE                  32,400
DISH NETWORK CORP             CL A              25470M109   2,078    72,950  SH      SOLE                  72,950
DOMINOS PIZZA INC             COM               25754A201   5,890   173,500  SH      SOLE                 173,500
DR PEPPER SNAPPLE GROUP INC   COM               26138E109   4,734   119,900  SH      SOLE                 119,900
DSW INC                       CL A              23334L102     455    10,300  SH      SOLE                  10,300
DU PONT E I DE NEMOURS & CO   COM               263534109   6,874   150,150  SH      SOLE                 150,150
DYCOM INDS INC                COM               267475101     678    32,400  SH      SOLE                  32,400
EASTMAN CHEM CO               COM               277432100   1,184    30,300  SH      SOLE                  30,300
EDUCATION MGMT CORP NEW       COM               28140M103     599    21,400  SH      SOLE                  21,400
EMCORE CORP                   COM               290846104      13    15,360  SH      SOLE                  15,360
ENI S P A                     SPONSORED ADR     26874R108   2,035    49,300  SH      SOLE                  49,300
ENPRO INDUSTRIES INC          COM               29355X107     376    11,400  SH      SOLE                  11,400
ENTERPRISE PRODS PARTNERS L P COM               293792107   2,342    50,500  SH      SOLE                  50,500
EXXON MOBIL CORP              COM               30231G102   1,678    19,800  SH      SOLE                  19,800
FAMILY DOLLAR STORES INC      COM               307000109   4,705    81,600  SH      SOLE                  81,600
FINISH LINE INC               CL A              317923100     478    24,800  SH      SOLE                  24,800
FOOT LOCKER INC               COM               344849104     572    24,000  SH      SOLE                  24,000
FOREST LABORATORIES           COM               345838106   1,446    47,800  SH      SOLE                  47,800
FRANCE TELECOM                SPONSORED ADR     35177Q105   1,496    95,500  SH      SOLE                  95,500
FREEPORT-MCMORAN COP & GOLD   COM               35671D857   1,225    33,300  SH      SOLE                  33,300
GAP INC                       COM               364760108   1,302    70,200  SH      SOLE                  70,200
GENERAL COMMUNICATION INC     CL A              369385109   2,643   270,000  SH      SOLE                 270,000
GENERAL DYNAMICS CORP         COM               369550108   1,428    21,500  SH      SOLE                  21,500
GENERAL ELECTRIC CO           COM               369604103   4,255   237,600  SH      SOLE                 237,600
GENERAL MILLS INC             COM               370334104   4,134   102,300  SH      SOLE                 102,300
GENESCO INC                   COM               371532102   5,767    93,400  SH      SOLE                  93,400
GENIE ENERGY LTD              CL B              372284208     927   116,900  SH      SOLE                 116,900
GENUINE PARTS CO              COM               372460105   5,159    84,300  SH      SOLE                  84,300
GILEAD SCIENCES INC           COM               375558103   1,613    39,400  SH      SOLE                  39,400
GLAXOSMITHKLINE PLC           SPONSORED ADR     37733W105   2,542    55,700  SH      SOLE                  55,700
GOODYEAR TIRE & RUBR CO       COM               382550101     444    31,300  SH      SOLE                  31,300
GRACE W R & CO                COM               38388F108     558    12,150  SH      SOLE                  12,150
GREENBRIER COS INC            COM               393657101   3,569   147,000  SH      SOLE                 147,000
GRUPO FINANCIERO GALICIA S A  SP ADR 10 SH B    399909100   1,291   217,700  SH      SOLE                 217,700
HARRIS CORP                   COM               413875105   1,182    32,800  SH      SOLE                  32,800
HCA HOLDINGS INC              COM               40412C101   1,024    46,500  SH      SOLE                  46,500
HEALTHSPRING INC              COM               42224N101     671    12,300  SH      SOLE                  12,300
HEINZ H J CO                  COM               423074103   2,453    45,400  SH      SOLE                  45,400
HEWLETT PACKARD CO            COM               428236103   1,007    39,100  SH      SOLE                  39,100
HOLLYFRONTIER CORP            COM               436106108     365    15,600  SH      SOLE                  15,600
HSN INC                       COM               404303109   4,877   134,500  SH      SOLE                 134,500
HUMANA INC                    COM               444859102   1,796    20,500  SH      SOLE                  20,500
IDT CORP                      CL B NEW          448947507   1,097   116,900  SH      SOLE                 116,900
INNOPHOS HOLDINGS INC         COM               45774N108     551    11,350  SH      SOLE                  11,350
INNOSPEC INC                  COM               45768S105   4,345   154,800  SH      SOLE                 154,800
INTEL CORP                    COM               458140100   9,940   409,900  SH      SOLE                 409,900
INTERFACE INC                 CL A              458665106   2,498   216,500  SH      SOLE                 216,500
INTERNATIONAL BUSINESS MACH   COM               459200101   1,747     9,500  SH      SOLE                   9,500
IPASS INC                     COM               46261V108      31    22,080  SH      SOLE                  22,080
ISTAR FINANCIALINC            COM               45031U101   2,552   482,500  SH      SOLE                 482,500
JABIL CIRCUIT INC             COM               466313103   4,732   240,700  SH      SOLE                 240,700
JOHNSON & JOHNSON             COM               478160104   7,224   110,150  SH      SOLE                 110,150
KELLOGG CO                    COM               487836108   2,266    44,800  SH      SOLE                  44,800
KEMET CORP                    COM NEW           488360207   1,845   261,700  SH      SOLE                 261,700
KIMBERLY CLARK CORP           COM               494368103   4,333    58,900  SH      SOLE                  58,900
KRAFT FOODS INC               CL A              50075N104   7,274   194,700  SH      SOLE                 194,700
KRISPY KREME DOUGHNUTS INC    COM               501014104   3,045   465,590  SH      SOLE                 465,590
KT CORP                       SPONSORED ADR     48268K101   1,559    99,700  SH      SOLE                  99,700
LAM RESEARCH CORP             COM               512807108   1,259    34,000  SH      SOLE                  34,000
LIBBEY INC                    COM               529898108   2,965   232,700  SH      SOLE                 232,700
LILLY ELI & CO                COM               532457108   4,368   105,100  SH      SOLE                 105,100
LIMITED BRANDS INC            COM               532716107   1,545    38,300  SH      SOLE                  38,300
LITHIA MOTORS INC             CL A              536797103     608    27,800  SH      SOLE                  27,800
LKQ CORP                      COM               501889208   5,059   168,200  SH      SOLE                 168,200
LOCKHEED MARTIN CORP          COM               539830109   4,183    51,700  SH      SOLE                  51,700
LSB INDS INC                  COM               502160104     356    12,700  SH      SOLE                  12,700
MACQUARIE INFRASTR CO LLC     MEMBERSHIP INT    55608B105     593    21,200  SH      SOLE                  21,200
MARSH & MCLENNAN COS INC      COM               571748102   2,713    85,800  SH      SOLE                  85,800
MATERION CORP                 COM               576690101   2,129    87,700  SH      SOLE                  87,700
MATTEL INC                    COM               577081102   4,261   153,500  SH      SOLE                 153,500
MCDONALDS CORP                COM               580135101   3,120    31,100  SH      SOLE                  31,100
MEDCATH CORP                  COM               58404W109   1,824   250,260  SH      SOLE                 250,260
MENS WEARHOUSE INC            COM               587118100     540    16,650  SH      SOLE                  16,650
MERCER INTL INC               COM               588056101   3,025   495,900  SH      SOLE                 495,900
MERCK & CO                    COM               58933Y105   7,851   208,250  SH      SOLE                 208,250
METROPCS COMMUNICATIONS       COM               591708102     286    32,900  SH      SOLE                  32,900
MICROSOFT CORP                COM               594918104   1,643    63,300  SH      SOLE                  63,300
MOBILE TELESYSTEMS            SPONSORED ADR     607409109   1,499   102,100  SH      SOLE                 102,100
MRV COMMUNICATIONS INC        COM               553477100      17    19,310  SH      SOLE                  19,310
MUELLER INDS INC              COM               624756102   4,620   120,250  SH      SOLE                 120,250
NACCO INDS INC                CL A              629579103   2,802    31,400  SH      SOLE                  31,400
NEW JERSEY RES                COM               646025106   5,156   104,800  SH      SOLE                 104,800
NEWCASTLE INVT CORP           COM               65105M108   2,645   568,900  SH      SOLE                 568,900
NEWMONT MINING CORP           COM               651639106   1,806    30,100  SH      SOLE                  30,100
NEWPORT CORP                  COM               651824104   2,683   197,100  SH      SOLE                 197,100
NISOURCE INC                  COM               65473P105   5,033   211,400  SH      SOLE                 211,400
NOKIA CORP                    SPONSORED ADR     654902204   1,022   212,000  SH      SOLE                 212,000
NORDSTROM INC                 COM               655664100   1,640    33,000  SH      SOLE                  33,000
ONEOK PARTNERS LP             UNIT LTD PARTN    68268N103   5,722    99,100  SH      SOLE                  99,100
OPNEXT INC                    COM               68375V105       9    10,710  SH      SOLE                  10,710
OXFORD INDS INC               COM               691497309     693    15,350  SH      SOLE                  15,350
PENSKE AUTOMOTIVE GRP INC     COM               70959W103     458    23,800  SH      SOLE                  23,800
PETROCHINA CO LTD             SPONSORED ADR     71646E100   2,101    16,900  SH      SOLE                  16,900
PETSMART INC                  COM               716768106   5,165   100,700  SH      SOLE                 100,700
PFIZER INC                    COM               717081103   8,624   398,500  SH      SOLE                 398,500
PHILIP MORRIS INTL INC        COM               718172109   2,888    36,800  SH      SOLE                  36,800
PIER 1 IMPORTS INC            COM               720279108   4,451   319,500  SH      SOLE                 319,500
PINNACLE WEST CAP CORP        COM               723484101   5,001   103,800  SH      SOLE                 103,800
PITNEY BOWES INC              COM               724479100   1,737    93,700  SH      SOLE                  93,700
POWER ONE INC NEW             COM               73930R102   1,182   302,300  SH      SOLE                 302,300
PRICESMART INC                COM               741511109  11,315   162,600  SH      SOLE                 162,600
PROCTER & GAMBLE CO           COM               742718109   3,883    58,200  SH      SOLE                  58,200
PROGRESSIVE CORP OHIO         COM               743315103   1,465    75,100  SH      SOLE                  75,100
QUAKER CHEM CORP              COM               747316107   3,203    82,360  SH      SOLE                  82,360
QUIKSILVER INC                COM               74838C106   2,393   663,000  SH      SOLE                 663,000
RAYTHEON CO                   COM NEW           755111507   3,846    79,500  SH      SOLE                  79,500
ROCHE HLDG LTD                ADR               771195104   2,566    60,300  SH      SOLE                  60,300
ROCKWOOD HLDGS INC            COM               774415103     384     9,750  SH      SOLE                   9,750
ROSS STORES INC               COM               778296103   5,238   110,200  SH      SOLE                 110,200
ROYAL DUTCH SHELL PLC         SPONSORED ADR A   780259206   2,441    33,400  SH      SOLE                  33,400
RUBY TUESDAY INC              COM               781182100   1,699   246,300  SH      SOLE                 246,300
SALLY BEAUTY HLDGS INC        COM               79546E104   6,244   295,500  SH      SOLE                 295,500
SANOFI-AVENTIS                SPONSORED ADR     80105N105   2,375    65,000  SH      SOLE                  65,000
SAUER-DANFOSS INC             COM               804137107   3,878   107,100  SH      SOLE                 107,100
SCANA CORP NEW                COM               80589M102   5,096   113,100  SH      SOLE                 113,100
SONIC AUTOMOTIVE INC          CL A              83545G102     561    37,850  SH      SOLE                  37,850
STATOIL ASA                   SPONSORED ADR     85771P102   2,633   102,800  SH      SOLE                 102,800
SUNOCO LOGISTICS PRTNRS L P   COM UNITS LP      86764L108   5,764   146,300  SH      SOLE                 146,300
SUNOPTA INC                   COM               8676EP108   2,158   447,800  SH      SOLE                 447,800
SYKES ENTERPRISES INC         COM               871237103     429    27,400  SH      SOLE                  27,400
SYSCO CORP                    COM               871829107   3,731   127,200  SH      SOLE                 127,200
TAIWAN SEMICONDUCTOR          SPONSORED ADR     874039100   2,551   197,600  SH      SOLE                 197,600
TELEDYNE TECHNOLOGIES INC     COM               879360105   4,832    88,100  SH      SOLE                  88,100
TELEFONICA S A                SPONSORED ADR     879382208   1,528    88,900  SH      SOLE                  88,900
TENNECO INC                   COM               880349105   2,427    81,500  SH      SOLE                  81,500
TESORO CORP                   COM               881609101   4,350   186,200  SH      SOLE                 186,200
TEXAS INSTRS INC              COM               882508104   1,339    46,000  SH      SOLE                  46,000
TIMKEN CO                     COM               887389104   3,902   100,800  SH      SOLE                 100,800
TITAN INTL INC ILL            COM               88830M102   3,532   181,500  SH      SOLE                 181,500
TJX COS INC NEW               COM               872540109   1,943    30,100  SH      SOLE                  30,100
TOTAL S A                     SPONSORED ADR     89151E109   2,080    40,700  SH      SOLE                  40,700
TOWERS WATSON & CO            CL A              891894107   4,509    75,232  SH      SOLE                  75,232
TPC GROUP INC                 COM               89236Y104   3,101   132,900  SH      SOLE                 132,900
TRACTOR SUPPLY CO             COM               892356106   5,493    78,300  SH      SOLE                  78,300
TRAVELERS COMPANIES INC       COM               89417E109   1,509    25,500  SH      SOLE                  25,500
TRIMAS CORP                   COM NEW           896215209   3,071   171,100  SH      SOLE                 171,100
TRIUMPH GROUP INC NEW         COM               896818101   5,377    92,000  SH      SOLE                  92,000
TRW AUTOMOTIVE HLDGS CORP     COM               87264S106   2,999    92,000  SH      SOLE                  92,000
TUESDAY MORNING CORP          COM NEW           899035505   2,105   610,100  SH      SOLE                 610,100
U S AIRWAYS GROUP INC         COM               90341W108   1,562   308,100  SH      SOLE                 308,100
UIL HLDG CORP                 COM               902748102   5,037   142,400  SH      SOLE                 142,400
UNITED CONTL HLDGS INC        COM               910047109   2,434   129,000  SH      SOLE                 129,000
UNITED RENTALS INC            COM               911363109   4,232   143,200  SH      SOLE                 143,200
UNITEDHEALTH GROUP INC        COM               91324P102   1,627    32,100  SH      SOLE                  32,100
UNIVERSAL STAINLESS & ALLOY   COM               913837100     483    12,930  SH      SOLE                  12,930
VALUEVISION MEDIA INC         CL A              92047K107     132    70,100  SH      SOLE                  70,100
VERIZON COMMUNICATIONS INC    COM               92343V104   8,461   210,900  SH      SOLE                 210,900
VODAFONE GROUP PLC            SPONSORED ADR NEW 92857W209   2,198    78,400  SH      SOLE                  78,400
WAL MART STORES INC           COM               931142103   1,739    29,100  SH      SOLE                  29,100
WALGREEN CO                   COM               931422109   1,203    36,400  SH      SOLE                  36,400
WASTE MGMT INC                COM               94106L109   2,044    62,500  SH      SOLE                  62,500
WESTAR ENERGY INC             COM               95709T100   4,993   173,500  SH      SOLE                 173,500
WESTELL TECH INC              CL A              957541105      23    10,580  SH      SOLE                  10,580
WESTERN REFNG INC             COM               959319104   4,550   342,400  SH      SOLE                 342,400
WORLD FUEL SVCS CORP          COM               981475106   5,222   124,400  SH      SOLE                 124,400
TOTAL                                                     567,829