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

                                  -------------

                                  SCHEDULE 13D
                                 (Rule 13d-101)

             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
            TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO
                                  RULE 13d-2(a)

                    Under the Securities Exchange Act of 1934
                            (Amendment No. ________)*

                             P.H. Glatfelter Company
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                                (Name of Issuer)

                     Common Stock, par value $.01 per share
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                         (Title of Class of Securities)

                                    377316104
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                                 (CUSIP Number)

                              Thomas R. Hudson Jr.
                               Pirate Capital LLC
                        200 Connecticut Avenue, 4th Floor
                                Norwalk, CT 06854
                                 (203) 854-1100
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                  (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                               September 19, 2006
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             (Date of Event which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following
box. |-|




NOTE: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for other parties
to whom copies are to be sent.

                         (Continued on following pages)

                               (Page 1 of 9 Pages)

----------

* The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

      The information required on the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the Act (however, see
the Notes).



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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 2 OF 9 PAGES
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--------------------------------------------------------------------------------
1     NAME OF REPORTING PERSON
      I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

      PIRATE CAPITAL LLC
--------------------------------------------------------------------------------
2     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) |_|
                                                                         (b) |X|

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3     SEC USE ONLY


--------------------------------------------------------------------------------
4     SOURCE OF FUNDS*

      AF
-----------------------------------------------------------------------------
5     CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
      ITEMS 2(d) or 2(e)                                                     |_|

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6     CITIZENSHIP OR PLACE OF ORGANIZATION

      Delaware
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                        7     SOLE VOTING POWER

                              -0-
                        --------------------------------------------------------
 NUMBER OF              8     SHARED VOTING POWER
  SHARES
BENEFICIALLY                  2,545,388
  OWNED BY              --------------------------------------------------------
    EACH                9     SOLE DISPOSITIVE POWER
 REPORTING
PERSON WITH                   -0-
                        --------------------------------------------------------
                        10    SHARED DISPOSITIVE POWER

                              2,545,388
--------------------------------------------------------------------------------
11    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

      2,545,388

--------------------------------------------------------------------------------
12    CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*     |_|


--------------------------------------------------------------------------------
13    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

      5.7%
--------------------------------------------------------------------------------
14    TYPE OF REPORTING PERSON*

      IA
--------------------------------------------------------------------------------
                     * SEE INSTRUCTIONS BEFORE FILLING OUT!



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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 3 OF 9 PAGES
-------------------                                            -----------------

--------------------------------------------------------------------------------
1     NAME OF REPORTING PERSON
      I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)

      THOMAS R. HUDSON JR.
--------------------------------------------------------------------------------
2     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                  (a) |_|
                                                                         (b) |X|

--------------------------------------------------------------------------------
3     SEC USE ONLY


--------------------------------------------------------------------------------
4     SOURCE OF FUNDS*

      AF
--------------------------------------------------------------------------------
5     CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
      ITEM 2(d) or 2(e)                                                      |_|

--------------------------------------------------------------------------------
6     CITIZENSHIP OR PLACE OF ORGANIZATION

      United States of America
--------------------------------------------------------------------------------
                        7     SOLE VOTING POWER

                              -0-
                        --------------------------------------------------------
 NUMBER OF              8     SHARED VOTING POWER
  SHARES
BENEFICIALLY                  2,545,388
  OWNED BY              --------------------------------------------------------
    EACH                9     SOLE DISPOSITIVE POWER
 REPORTING
PERSON WITH                   -0-
                        --------------------------------------------------------
                        10    SHARED DISPOSITIVE POWER

                              2,545,388
--------------------------------------------------------------------------------
11    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

      2,545,388
--------------------------------------------------------------------------------
12    CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*     |_|


--------------------------------------------------------------------------------
13    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

      5.7%
--------------------------------------------------------------------------------
14    TYPE OF REPORTING PERSON*

      IN
--------------------------------------------------------------------------------
                     * SEE INSTRUCTIONS BEFORE FILLING OUT!



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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 4 OF 9 PAGES
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ITEM 1. SECURITY AND ISSUER

This Schedule 13D relates to the shares of common stock, par value $.01 per
share (the "Shares"), of P.H. Glatfelter Company (the "Issuer"). The principal
executive office of the Issuer is located at 96 South George Street, Suite 500,
York, Pennsylvania 17401.

ITEM 2. IDENTITY AND BACKGROUND

      (a) This statement is filed by Pirate Capital LLC, a Delaware limited
liability company ("Pirate Capital"), and Thomas R. Hudson Jr. (together with
Pirate Capital, the "Reporting Persons"). Each of the Reporting Persons is
deemed to be the beneficial owner of the Shares held by Jolly Roger Fund LP,
Jolly Roger Offshore Fund LTD and Jolly Roger Activist Portfolio Company LTD
(together, the "Holders"). The Reporting Persons disclaim that they and/or the
Holders are members of a group as defined in Regulation 13D-G.

      (b) The principal business address of the Reporting Persons is 200
Connecticut Avenue, 4th Floor, Norwalk, Connecticut 06854.

      (c) The principal business of Pirate Capital is providing investment
management services to investment partnerships and other entities. The principal
occupation or employment of Thomas R. Hudson Jr. is serving as the sole owner
and Managing Member of Pirate Capital.

      (d) Neither of the Reporting Persons has, during the last five years, been
convicted in a criminal proceeding (excluding traffic violations or similar
misdemeanors).

      (e) Neither of the Reporting Persons has, during the last five years, been
a party to a civil proceeding of a judicial or administrative body of competent
jurisdiction and as a result of such proceeding was or is subject to a judgment,
decree or final order enjoining future violations of, or prohibiting or
mandating activities subject to, federal or state securities laws or finding any
violation with respect to such laws.

      (f) Thomas R. Hudson Jr. is a citizen of the United States of America.

ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION

Funds for the purchase of the Shares were derived from available capital of the
Holders. A total of approximately $34,419,586 was paid to acquire the Shares
reported herein.



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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 5 OF 9 PAGES
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ITEM 4. PURPOSE OF TRANSACTION

The Reporting Persons originally acquired Shares of the Issuer for investment in
the ordinary course of business because they believed that the Shares, when
purchased, were undervalued and represented an attractive investment
opportunity.

Except as set forth herein or as would occur upon completion of any of the
actions discussed herein, the Reporting Persons have no present plan or proposal
that would relate to or result in any of the matters set forth in subparagraphs
(a)-(j) of Item 4 of Schedule 13D. The Reporting Persons intend to review their
investment in the Issuer on a continuing basis and may engage in discussions
with management, the Board of Directors, other shareholders of the Issuer and
other relevant parties concerning the business, operations, board composition,
management, strategy and future plans of the Issuer. Depending on various
factors including, without limitation, the Issuer's financial position and
strategic direction, the outcome of the discussions and actions referenced
above, actions taken by the Board of Directors, price levels of the Shares,
other investment opportunities available to the Reporting Persons, conditions in
the securities market and general economic and industry conditions, the
Reporting Persons may in the future take such actions with respect to their
investment in the Issuer as they deem appropriate including, without limitation,
purchasing additional Shares or selling some or all of their Shares, engaging in
short selling of or any hedging or similar transactions with respect to the
Shares and/or otherwise changing their intention with respect to any and all
matters referred to in Item 4 of Schedule 13D.

ITEM 5. INTEREST IN SECURITIES OF THE ISSUER

      (a) The Reporting Persons beneficially own 2,545,388 Shares, constituting
approximately 5.7% of the Shares outstanding, based upon 44,736,167 Shares
stated to be outstanding in the Issuer's Quarterly Report on Form 10-Q/A for the
quarter ended June 30, 2006.

      (b) By virtue of its position as general partner of Jolly Roger Fund LP,
Pirate Capital has the power to vote or direct the voting, and to dispose or
direct the disposition, of all of the 115,800 Shares held by Jolly Roger Fund
LP. By virtue of agreements with Jolly Roger Offshore Fund LTD and Jolly Roger
Activist Portfolio Company LTD, Pirate Capital has the power to vote or direct
the voting, and to dispose or direct the disposition, of all of the 2,429,588
Shares held by Jolly Roger Offshore Fund LTD and Jolly Roger Activist Portfolio
Company LTD. By virtue of his position as sole Managing Member of Pirate
Capital, Thomas R. Hudson Jr. is deemed to have shared voting power and shared
dispositive power with respect to all Shares as to which Pirate Capital has
voting power or dispositive power. Accordingly, Pirate Capital and Thomas R.
Hudson Jr. are deemed to have shared voting and shared dispositive power with
respect to an aggregate of 2,545,388 Shares.

      (c) The following transactions in the Shares were effected by the
Reporting Persons during the past 60 days, each of which was effected in open
market transactions.

Jolly Roger Activist Portfolio Company LTD

Trade Date                 Shares Purchased (Sold)           Price per Share ($)
----------                 -----------------------           ------------------
 9/15/2006                           30,300                       14.12
 9/19/2006                          200,000                       13.68
 9/21/2006                           75,000                       13.25
 9/21/2006                           25,000                       13.35
 9/22/2006                           85,100                       13.10

Jolly Roger Offshore Fund LTD

Trade Date                 Shares Purchased (Sold)           Price per Share ($)
----------                 -----------------------           -------------------

 8/08/2006                          150,000                      14.99
 8/10/2006                           20,000                      13.50
8/10/2006                            20,000                      13.50
8/10/2006                            44,900                      13.50
8/10/2006                           (25,000)                     13.32
8/10/2006                           116,400                      13.50
8/10/2006                            55,000                      13.48
8/10/2006                            25,000                      13.48
8/10/2006                             4,198                      13.60
8/10/2006                             9,790                      13.60
8/10/2006                           100,000                      14.05





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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 6 OF 9 PAGES
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      (d) No person other than the Reporting Persons and the Holders is known to
have the right to receive or the power to direct the receipt of dividends from,
or the proceeds from the sale of, such Shares.

      (e) Not applicable.

ITEM 6. CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT TO
SECURITIES OF THE ISSUER

Except as otherwise set forth herein, the Reporting Persons do not have any
contract, arrangement, understanding or relationship with any person with
respect to the securities of the Issuer.

ITEM 7. MATERIAL TO BE FILED AS EXHIBITS

      See Exhibit Index hereto.



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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 7 OF 9 PAGES
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                                   SIGNATURES

After reasonable inquiry and to the best of each of the undersigned's knowledge
and belief, each of the undersigned certifies that the information set forth in
this statement is true, complete and correct.

Dated: September 26, 2006

                                        PIRATE CAPITAL LLC


                                        By: /s/ Thomas R. Hudson Jr.
                                            ---------------------------
                                            Name: Thomas R. Hudson Jr.
                                            Title: Managing Member


                                        /s/ Thomas R. Hudson Jr.
                                        -------------------------------
                                        Thomas R. Hudson Jr.



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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 8 OF 9 PAGES
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                                  EXHIBIT INDEX

      1.    Exhibit A - Joint Acquisition Statement, dated September 26, 2006





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CUSIP NO. 377316104               SCHEDULE 13D                 PAGE 9 OF 9 PAGES
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                                    EXHIBIT A

                           JOINT ACQUISITION STATEMENT

                            PURSUANT TO RULE 13d-1(k)

      The undersigned acknowledge and agree that the foregoing statement on
Schedule 13D is filed on behalf of each of the undersigned, and that all
subsequent amendments to this statement on Schedule 13D shall be filed on behalf
of each of the undersigned without the necessity of filing additional joint
acquisition statements. The undersigned acknowledge that each shall be
responsible for the timely filing of such amendments, and for the completeness
and accuracy of the information concerning him or it contained therein, but
shall not be responsible for the completeness and accuracy of the information
concerning the other, except to the extent that he or it knows or has reason to
believe that such information is inaccurate.


Dated: September 26, 2006

                                        PIRATE CAPITAL LLC


                                        By: /s/ Thomas R. Hudson Jr.
                                            ---------------------------
                                            Name: Thomas R. Hudson Jr.
                                            Title: Managing Member


                                        /s/ Thomas R. Hudson Jr.
                                        -------------------------------
                                        Thomas R. Hudson Jr.