Exhibit 4.3

|NUMBER                                               |     |  |  | SHARES                             
|---------------------------------------------------- | --- |  |  | -----------------------------------
|                                                     | CSD |  |  |                                    
|PETCO LOGO                                          
|INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE |     |  |  | SEE REVERSE FOR
CERTAIN DEFINITIONS
|                                                     |     |  |  | CUSIP 716016 20 9                  

This
certifies that
   
   
   
   
   
   
is the record holder of

FULLY
PAID AND NONASSESSABLE SHARES OF THE COMMON STOCK, PAR VALUE $.001 PER SHARE, OF

| | PETCO ANIMAL SUPPLIES, INC. | 
| | --------------------------- | 

transferable on the books of the Corporation in person or by duly authorized attorney upon surrender of this Certificate properly endorsed.

This
Certificate is not valid until countersigned by the Transfer Agent and registered by the Registrar.

WITNESS
the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers.

|Dated:                                                             |  |  |  |                                                                  
|------------------------------------------------------------------ |  |  |  | -----------------------------------------------------------------
|PETCO ANIMAL SUPPLIES, INC.
CORPORATE
SEAL
APRIL 19, 1991
DELAWARE
|/s/JAMES M. MYERSSecretary                                         |  |  |  | /s/BRIAN K. DEVINEChairman, President and
Chief Executive Officer

| |  | COUNTERSIGNED AND REGISTERED: AMERICAN STOCK TRANSFER & TRUST COMPANYTRANSFER AGENT AND REGISTRAR
| |  | -------------------------------------------------------------------------------------------------
| |  | By                                                                                               
| |  | AUTHORIZED SIGNATURE                                                                             

---

The
Corporation shall furnish without charge to each stockholder who so requests a statement of the powers, designations, preferences and relative, participating, optional or other
special rights of each class of stock of the Corporation or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights. Such requests shall be made to the
Corporation's Secretary at the principal office of the Corporation.

The
following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or
regulations:

|TEN COM | as tenants in common                                                     |  | UNIF GIFT MIN ACT | (Cust)                                       |  | Custodian                   |  | (Minor)
|-------- | ------------------------------------------------------------------------ |  | ------------------ | -------------------------------------------- |  | --------------------------- |  | -------
|TEN ENT | as tenants by the entireties                                             |  |                    | under Uniform Gifts to Minors Act(State)    
|JT TEN  | as joint tenants with right of survivorship and not as tenants in common |  | UNIF TRF MIN ACT  | (Cust)                                       |  | Custodian (until age      ) |  | (Minor)
|         |                                                                          |  |                    | under Uniform Transfers to Minors Act(State)

Additional abbreviations may also be used though not in the above list.

---

For value received,
                        hereby sell, assign and transfer unto

|Please Insert Social Security Or Other
Identifying Number of Assignee                                                    |          |  | 
|------------------------------------------------------------------------------------------------------------------------ | -------- |  | 
|                                                                                                                        
|(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS INCLUDING POSTAL ZIP CODE OF ASSIGNEE)                                      
|                                                                                                                        
|                                                                                                                        
|                                                                                                                         | Shares  
|of the common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint             
|                                                                                                                         | Attorney
|to transfer the said stock on the books of the within named Corporation with full power of substitution in the premises.

|Dated, |  |  |         |  |                                                                                                                                                                                               
|------ |  |  | ------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|       |  |  | X       |  |                                                                                                                                                                                               
|       |  |  | X       |  |                                                                                                                                                                                               
|       |  |  | NOTICE: |  | THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME(S) AS WRITTEN UPON THE FACE OF THE CERTIFICATE, IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT, OR ANY CHANGE WHATEVER.

|Signature(s) Guaranteed: |                                                                                                                                                                                                                                                           | 
|------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | 
|By                       | THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION, (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE
GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17AD-15. | 

---

QuickLinks