**Exhibit 31.1**

 

**CERTIFICATION**

 

I, Robert Kaminski, certify that:

 

I have reviewed this annual report on Form 10-K of LEINER HEALTHPRODUCTS Inc.

 

Based on my knowledge, this report does not contain any untruestatement of a material fact or omit to state a material fact necessary to makethe statements made, in light of the circumstances under which such statementswere made, not misleading with respect to the period covered by this report;

 

Based on my knowledge, the financial statements, and other financialinformation included in this report, fairly present in all material respectsthe financial condition, results of operations and cash flows of LEINER HEALTHPRODUCTS Inc. as of, and for, the periods presented in this report;

 

LEINER HEALTH PRODUCTS Inc.’s other certifying officer and I areresponsible for establishing and maintaining disclosure controls and procedures(as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) andinternal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and15d-15(f)) for  LEINER HEALTH PRODUCTSInc. and have:

 

(a)                        Designedsuch disclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to LEINER HEALTH PRODUCTS Inc., including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

 

(b)                       Designedsuch internal control over financial reporting, or caused such internal controlover financial reporting to be designed under our supervision, to providereasonable assurance regarding the reliability of financial reporting and thepreparation of financial statements for external purposes in accordance withgenerally accepted accounting principles;

 

(c)                        Evaluatedthe effectiveness of  LEINER HEALTHPRODUCTS Inc.’s disclosure controls and procedures and presented in this reportour conclusions about the effectiveness of the disclosure controls and procedures,as of the end of the period covered by this report based on such evaluation;and

 

(d)                       Disclosedin this report any change in LEINER HEALTH PRODUCTS Inc.’s internal controlover financial reporting that occurred during LEINER HEALTH PRODUCTS Inc.’s mostrecent fiscal quarter that has materially affected, or is reasonably likely tomaterially affect, LEINER HEALTH PRODUCTS Inc.’s internal control overfinancial reporting; and

 

LEINER HEALTH PRODUCTS Inc.’s other certifying officer and I havedisclosed, based on our most recent evaluation of internal control overfinancial reporting, to LEINER HEALTH PRODUCTS Inc.’s auditors and the auditcommittee of LEINER HEALTH PRODUCTS Inc.’s board of directors (or personsperforming the equivalent functions):

 

(a)                        All significant deficienciesand material weaknesses in the design or operation of internal control overfinancial reporting which are reasonably likely to adversely affect LEINERHEALTH PRODUCTS Inc.’s ability to record, process, summarize and report financialinformation; and

 

(b)                       Any fraud, whether or notmaterial, that involves management or other employees who have a significantrole in LEINER HEALTH PRODUCTS Inc.’s internal controls over financialreporting.

 
| Date: June 24, 2005 |
|--------------------------|
|                     |
| /s/ Robert Kaminski      |   |
| Robert Kaminski          |
| Chief Executive Officer  |

 

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