**As filed with the Securities and Exchange Commission on  October 15, 2009**

**Registration  No. 333-158237**

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

**POST-EFFECTIVE  AMENDMENT NO. 1****TO****FORM S-4**

**REGISTRATION  STATEMENT**

**ON**

**FORM S-8**

**UNDER THE SECURITIES ACT OF 1933**

**PFIZER INC.**(Exact Name of Registrant  as Specified in Its Charter) 

| **Delaware**        (State or Other Jurisdiction of        Incorporation or Organization) |   | **13-5315170**      (I.R.S. Employer      Identification No.) |
|-------------------------------------------------------------------------------------------|--------|---------------------------------------------------------------|

**235 EAST    42ND STREET****NEW YORK****, NEW    YORK 10017-5755**(Address of Principal Executive Offices)

**Wyeth Amended and  Restated 2005 Stock Incentive Plan  Wyeth 2002 Stock Incentive Plan  Wyeth 1999 Stock Incentive Plan  Wyeth 1996 Stock Incentive Plan  Wyeth Management Incentive Plan**  (Full Title of the Plans)**Amy Schulman    Senior Vice President and General Counsel****Pfizer Inc.    235 East 42nd Street    New York, New York 10017**  (Name and Address of Agent for Service)**(212) 733-2323**  (Telephone Number, including area code, of Agent for Service)****

 Indicate by check  mark whether the registrant is a large accelerated filer, an accelerated filer,  a non-accelerated filer or a smaller reporting company. See definitions of  "large accelerated filer," "accelerated filer" and "smaller reporting company"  in Rule 12b-2 of the Exchange Act.****

| Large accelerated filer x                     |   | Accelerated filer o         |
|----------------------------------------------------|--------|----------------------------------|
|                                               |   |                             |
| Non-accelerated filer o                       |   | Smaller reporting company o |
| (Do not check if a smaller reporting      company) |   |                             |

**CALCULATION OF REGISTRATION  FEE**

| **Title of Securities to be      Registered** | **Amount to     be        Registered(1)(2)** | **Proposed Maximum Offering        Price Per Share(3)** | **Proposed Maximum Aggregate        Offering Price(3)** | **Amount of     Registration Fee(3)** |
|-----------------------------------------------|----------------------------------------------|---------------------------------------------------------|---------------------------------------------------------|---------------------------------------|
| Common Stock, par value $.05 par value        | 2,050,000 shares                             | N/A                                                     | N/A                                                     | N/A                                   |

(1)   The number of  shares registered is based on an estimate of the maximum number of shares of  common stock of Pfizer Inc. ("Pfizer") issuable by Pfizer with respect to  certain equity-based awards that are outstanding under the Wyeth Amended and  Restated 2005 Stock Incentive Plan, the Wyeth 2002 Stock Incentive Plan, the Wyeth  1999 Stock Incentive Plan, the Wyeth 1996 Stock Incentive Plan and the Wyeth  Management Incentive Plan (collectively, the "Plans").

  (2)   Pursuant to  Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement shall be  deemed to cover an indeterminate amount of additional shares that may become  issuable as a result of stock splits, stock dividends or similar transactions  pursuant to the anti-dilution provisions of the Plans.  (3)   The proposed  maximum offering price was calculated and the fee was previously paid in  connection with the filing with the U.S. Securities and Exchange Commission  (the"Commission") of the Registration Statement on Form S-4 of Pfizer (File  No. 333-158237) on March 27, 2009.

**Explanatory  Note**

                Pfizer  hereby amends its Registration Statement on Form S-4 (File No. 333-158237), as  amended by Amendments No. 1, 2 and 3, which was declared effective on June 17,  2009 (the "Form S-4"), by filing this Post-Effective Amendment No. 1 on Form  S-8 (the"“Post-Effective Amendment") relating to shares of Pfizer common stock,  par value $0.05 per share (the "Pfizer Common Stock"), that are issuable by  Pfizer with respect to certain Wyeth equity-based awards that are outstanding  under the Plans.  All such shares of  Pfizer Common Stock were originally registered on the Form S-4.  Pfizer filed the Form S-4 in connection with  the merger contemplated by the Agreement and Plan of Merger, dated as of  January 25, 2009, as amended (the "Merger Agreement"), by and among Pfizer,  Wagner Acquisition Corp. ("Merger Sub") and Wyeth.  

                On October  15, 2009, pursuant to the Merger Agreement, Merger Sub merged with and into  Wyeth, with Wyeth surviving the merger (the "Merger") as a wholly owned subsidiary  of Pfizer.  As a result of the Merger,  each share of Wyeth common stock, par value $0.33 1/3 per  share (the "Wyeth Common Stock") (other than shares of restricted stock (which  received cash consideration pursuant to the terms of the Merger Agreement),  shares of Wyeth Common Stock held directly or indirectly by Wyeth or Pfizer  (which were cancelled as a result of the Merger) and shares with respect to  which appraisal rights were properly exercised and not withdrawn) was converted  into the right to receive a combination of $33.00 in cash and 0.985 of a  validly issued, fully paid and non-assessable share of Pfizer Common Stock,  without interest and less any applicable withholding tax (the “Merger  Consideration”).  In connection  therewith, certain Wyeth equity-based awards issued under the Plans that could  not be immediately settled following consummation of the Merger were converted  into the right to receive Merger Consideration in respect of each share of Wyeth  Common Stock into which such awards would otherwise be convertible.  Holders of such equity-based awards will  receive the Merger Consideration at a future date in accordance with and  subject to the terms of the respective Plans.

**PART I.**

**INFORMATION REQUIRED IN THE  SECTION 10(a) PROSPECTUS**

The document(s) containing the information specified  in Part I of Form S-8 have been or will be sent or given to participants in the  Plans as specified by Rule 428(b)(1) under the Securities Act. These documents  and the documents incorporated by reference into this Registration Statement  pursuant to Item 3 of Part II of this Registration Statement, taken together,  constitute a prospectus that meets the requirements of Section 10(a) of the  Securities Act. 

**PART II.**

**INFORMATION REQUIRED IN THE REGISTRATION  STATEMENT**

**ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.**

The following documents filed with the Commission are hereby  incorporated by reference in this Registration Statement:   Pfizer's Annual Report on Form 10-K for the year  ended December 31, 2008;   Pfizer's Quarterly Reports on Form 10-Q for the  quarters ended March 29, 2009 and June 28, 2009;  Pfizer's Current Reports on Form 8-K filed  January 14, 2009, January 26, 2009, January 29, 2009, February 20, 2009, March  12, 2009, March 13, 2009, April 7, 2009, April 27, 2009, April 28, 2009, June  3, 2009, July 17, 2009, July 22, 2009, September 2, 2009, September 25, 2009  and October 15, 2009; and the description of Pfizer’s common stock  contained in our Registration Statement filed under Section 12 of the  Exchange Act on March 1, 2004, including all amendments and reports updating  the description. 

  All documents filed by Pfizer under Section 13(a), 13(c), 14,  and 15(d) of the Exchange Act after the date of this Registration Statement and  prior to the filing of a post-effective amendment to this Registration  Statement indicating that all securities offered have been sold or that  deregisters the distribution of all securities then remaining unsold, will be  deemed to be incorporated by reference into this Registration Statement and  will be a part of this Registration Statement from the date that document was  filed.  Any statement contained in a  document incorporated or deemed to be incorporated by reference herein shall be  deemed to be modified or superseded for the purposes of this Registration  Statement to the extent that a statement contained in this Registration  Statement or in any other subsequently filed document that also is or is deemed  to be incorporated by reference herein modifies or supersedes such  statement.  Any statement so modified or  superseded shall not be deemed, except as so modified or superseded, to  constitute a part of this Registration Statement.  Pfizer's Exchange Act file number with the  Commission is 001-03619.

**ITEM 4. DESCRIPTION OF SECURITIES**

Not applicable.

**ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL**

The validity of the securities has been passed  upon by Amy Schulman, Senior Vice President and General Counsel of Pfizer.  Ms. Schulman beneficially owns shares of  Pfizer common stock and options to purchase Pfizer common stock under Pfizer's  2004 Stock Plan.

**ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS**

The following is only a general summary of certain aspects of  Delaware law and Pfizer's Restated Certificate of Incorporation and By-laws related  to indemnification of directors and officers, and does not purport to be  complete. It is qualified in its entirety by reference to the detailed  provisions of Sections 145 and 102(b)(7) of the Delaware General Corporation  Law (the "DGCL"), Article 7(14) of Pfizer’s Restated Certificate of  Incorporation and Article V of Pfizer's By-laws.   Section 145 of the DGCL generally provides that all directors  and officers (as well as other employees and individuals) may be indemnified  against expenses (including attorneys' fees), judgments, fines and amounts paid  in settlement in connection with certain specified actions, suits or  proceedings, whether civil, criminal, administrative or investigative (other  than an action by or in the right of the corporation, or a derivative action),  if they acted in good faith and in a manner they reasonably believed to be in  or not opposed to the best interests of the corporation, and, with respect to  any criminal action or proceeding, had no reasonable cause to believe their conduct  was unlawful. A similar standard of care is applicable in the case of  derivative actions, except that indemnification extends only to expenses  (including attorneys' fees) incurred in connection with defense or settlement  of an action, and the DGCL requires court approval before there can be any  indemnification where the person seeking indemnification has been found liable  to the corporation. Section 145 of the DGCL also provides that the rights  conferred thereby are not exclusive of any other right to which any person may  be entitled under any bylaw, agreement, vote of stockholders or disinterested  directors or otherwise, and permits a corporation to advance expenses to or on  behalf of a person entitled to be indemnified upon receipt of an undertaking to  repay the amounts advanced if it is determined that the person is not entitled  to be indemnified.   Article V of Pfizer's By-laws provides that Pfizer will  indemnify and hold harmless, to the fullest extent permitted by applicable law  as it presently exists or may be amended, any person who was or is made or is  threatened to be made a party to or is otherwise involved in any action, suit  or proceeding, whether civil, criminal, administrative or investigative, by  reason of the fact that he or she, or a person for whom he or she is the legal  representative, is or was a director, officer, employee or agent of Pfizer or  is or was serving at the request of Pfizer as a director, officer, employee or  agent of another corporation or of a partnership, joint venture, trust,  nonprofit entity, or other enterprise, including service with respect to  employee benefit plans, against all liability and loss suffered and expenses  (including attorneys' fees) reasonably incurred by such person. Pfizer is  required to indemnify a person in connection with a proceeding initiated by  such person only if the proceeding was authorized by the Pfizer Board of  Directors. In addition, Pfizer will pay the expenses (including attorneys'  fees) incurred by an officer or director of Pfizer in defending any proceeding  in advance of its final disposition, provided, however, that the payment of  such expenses will be made only upon receipt of an undertaking by the director  or officer to repay all amounts advanced if it is ultimately determined that  the director or officer is not entitled to be indemnified. Pfizer has entered  into agreements with its directors and certain of its officers requiring Pfizer  to indemnify such persons to the fullest extent permitted by Pfizer's By-laws.  As permitted by Section 102(b)(7) of the DGCL, Pfizer’s  Restated Certificate of Incorporation, in Article 7(14), provides that no  director shall be personally liable to Pfizer or its stockholders for monetary  damages for breach of fiduciary duty as a director other than (i) for any  breach of the director’s duty of loyalty to Pfizer and its stockholders, (ii)  for acts or omissions not in good faith or which involve intentional misconduct  or a knowing violation of law, (iii) under Section 174 of the DGCL, and (iv)  for any transaction from which the director derived an improper personal  benefit. As permitted by Section 145(g) of the DGCL, Pfizer also  maintains directors' and officers' insurance policies that insure the directors  and officers of Pfizer against liability asserted against such persons in such  capacity whether or not such directors or officers have the right to  indemnification pursuant to the By-laws or otherwise.

**ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED**

Not applicable.

**ITEM 8. EXHIBITS**

| **Exhibit Number** | **Exhibit**                                                                                       |
|--------------------|---------------------------------------------------------------------------------------------------|
| 23(i)              | Consent of KPMG    LLP, Independent Registered Public Accounting Firm of Pfizer*                  |
| 23(ii)             | Consent of PricewaterhouseCoopers    LLP, Independent Registered Public Accounting Firm of Wyeth* |
| 24                 | Powers of Attorney**                                                                              |

_________  *Filed herewith  **Previously filed

**ITEM 9. UNDERTAKINGS**

The undersigned Registrant hereby undertakes:

(1) To file, during any period in which offers or  sales are being made, a post-effective amendment to this Registration  Statement:

(i) To include any prospectus required by Section 10(a)(3)  of the Securities Act;

(ii) To reflect in the prospectus any facts or events  arising after the effective date of the Registration Statement (or the most  recent  post-effective amendment thereof) which, individually or in the  aggregate, represent a fundamental change in the information set forth in the  Registration Statement.  Notwithstanding  the foregoing, any increase or decrease in volume of securities offered (if the  total dollar value of securities offered would not exceed that which was  registered) and any deviation from the low or high end of the estimated maximum  offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the  aggregate, the changes in volume and price represent no more than 20% change in  the maximum aggregate offering price set forth in the "Calculation  of Registration Fee" table in the effective Registration Statement; and

(iii) To  include any material information with respect to the plan of distribution not  previously disclosed in the registration statement or any material change to  such information in the registration statement;

*provided*,*however*,  that paragraphs (1)(i) and (1)(ii) do not apply to this Registration Statement  on FormS-8 to the extent that the information required to be included in a  post-effective amendment by those paragraphs is contained in reports filed with  or furnished to the Commission by the Registrant pursuant to Section 13 or  Section15(d) of the Exchange Act that are incorporated by reference in the  Registration Statement.

(2) That, for purposes of determining any liability  under the Securities Act, each such post-effective amendment shall be deemed to  be a new registration statement relating to the securities offered herein, and  the offering of such securities at that time shall be deemed to be the initial  bona fide offering thereof

(3) To remove from registration by means of a  post-effective amendment any of the securities being registered which remain  unsold at the termination of the offering.

(4) The undersigned Registrant hereby undertakes  that, for purposes of determining any liability under the Securities Act, each  filing of Pfizer’s annual report pursuant to section 13(a) or section 15(d) of  the Exchange Act  that is incorporated by reference in the Registration  Statement shall be deemed to be a new registration statement relating to the  securities offered therein, and the offering of such securities at that time  shall be deemed to be the initial bona fide offering thereof.

(5) Insofar as  indemnification for liabilities arising under the Securities Act may be  permitted to directors, officers and controlling persons of the Registrant  pursuant to the foregoing provisions, or otherwise, the Registrant has been  advised that in the opinion of the Commission such indemnification is against  public policy as expressed in the Securities Act and is, therefore  unenforceable.  In the event that a claim  for indemnification against such liabilities (other than the payment by the  Registrant of expenses incurred or paid by a director, officer or controlling  person of the Registrant in the successful defense of any action, suit or  proceeding) is asserted by such director, officer or controlling person in  connection with the securities being registered, the Registrant will, unless in  the opinion of its counsel the matter has been settled by controlling  precedent, submit to a court of  appropriate jurisdiction the question  whether such  indemnification by it is against public policy as expressed  in the Securities Act and will be governed by the final adjudication of such issue.

____________________________________________________________________________________

**SIGNATURES**

Pursuant to the requirements of the Securities Act, the  Registrant certifies that it has reasonable grounds to believe that it meets  all of the requirements for filing on Form S-8 and has duly caused this  Registration Statement to be signed on its behalf by the undersigned, thereunto  duly authorized, in The City of New York, State of New York, on the 15th  day of October, 2009.

> 
      PFIZER INC.      By:        /s/Frank  A. D’Amelio      Name:  Frank A. D’Amelio       Title:     Senior Vice President and  Chief Financial Officer

  We, the undersigned directors and officers of Pfizer Inc.,  hereby severally constitute Amy W. Schulman and Matthew Lepore, and each of  them singly, our true and lawful attorneys with full power to them and each of  them to sign for us, in our names in the capacities indicated below, any and  all amendments (including post-effective amendments) to this Registration  Statement filed with the Securities and Exchange Commission.

 

| **SIGNATURE**                                                 | **TITLE**                                                                                       | **DATE**         |
|---------------------------------------------------------------|-------------------------------------------------------------------------------------------------|------------------|
| /s/ Jeffrey B. Kindler*      (Jeffrey B. Kindler)             | Chairman of the Board, Chief Executive Officer and Director       (Principal Executive Officer) | October 15, 2009 |
| /s/    Frank A. D’Amelio      (Frank A. D’Amelio) | Senior    Vice President and       Chief Financial Officer       (Principal Financial Officer)  | October 15, 2009 |
| /s/    Loretta V. Cangialosi*      (Loretta V. Cangialosi)    | Senior    Vice President - Controller      (Principal Accounting Officer)                       | October 15, 2009 |
| /s/    Dennis A. Ausiello*      (Dennis A. Ausiello)          | Director                                                                                        | October 15, 2009 |
| /s/    Michael S. Brown*      (Michael S. Brown)              | Director                                                                                        | October 15, 2009 |
| /s/    M. Anthony Burns*      (M. Anthony Burns)              | Director                                                                                        | October 15, 2009 |
| /s/    Robert N. Burt*      (Robert N. Burt)                  | Director                                                                                        | October 15, 2009 |
| /s/    W. Don Cornwell*      (W. Don Cornwell)                | Director                                                                                        | October 15, 2009 |
| /s/    William H. Gray, III*      (William H. Gray, III)      | Director                                                                                        | October 15, 2009 |
| /s/    Constance J. Horner*      (Constance J. Horner)        | Director                                                                                        | October 15, 2009 |

| /s/    Suzanne Nora Johnson*      (Suzanne Nora Johnson) | Director | October 15, 2009 |
|----------------------------------------------------------|----------|------------------|

_____________________________________________________________________________

| **SIGNATURE** | **TITLE** | **DATE** |
|---------------|-----------|----------|

| /s/    James M. Kilts*      (James M. Kilts)                 | Director | October 15, 2009 |
|--------------------------------------------------------------|----------|------------------|
| /s/    George A. Lorch*      (George A. Lorch)               | Director | October 15, 2009 |
| /s/    Dana G. Mead*      (Dana G. Mead)                     | Director | October 15, 2009 |
| /s/    Stephen W. Sanger*      (Stephen W. Sanger)           | Director | October 15, 2009 |
| /s/    William C. Steere, Jr.*      (William C. Steere, Jr.) | Director | October 15, 2009 |

***By:/**s/Matthew  Lepore**Name:**Matthew Lepore**Title: **Attorney-in-Fact

_____________________________________________________________________________________

**EXHIBIT INDEX**

| Exhibit Number | Exhibit                                                                                              |
|----------------|------------------------------------------------------------------------------------------------------|
| 23(i)          | Consent of KPMG    LLP, Independent Registered Public Accounting Firm of Pfizer*                     |
| 23(ii)         | Consent of    PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm of    Wyeth* |
| 24             | Powers of    Attorney**                                                                              |

_________  *Filed herewith  **Previously filed