EXHIBIT 31(A)

                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
               PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT

     I, William C. Weldon, certify that:

          1.  I have reviewed this annual report on Form 10-K of Johnson &
     Johnson (the "Company");

          2.  Based on my knowledge, this annual report does not contain any
     untrue statement of a material fact or omit to state a material fact
     necessary to make the statements made, in light of the circumstances under
     which such statements were made, not misleading with respect to the period
     covered by this report;

          3.  Based on my knowledge, the financial statements, and other
     financial information included in this annual report, fairly present in all
     material respects the financial condition, results of operations and cash
     flows of the Company as of, and for, the periods presented in this report;

          4.  The Company's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e)) and internal control over financial
     reporting (as defined in Exchange Act Rules 13a-15(f)) for the Company and
     have:

             a) Designed such disclosure controls and procedures, or caused such
        disclosure controls and procedures to be designed under our supervision,
        to ensure that material information relating to the Company, including
        its consolidated subsidiaries, is made known to us by others within
        those entities, particularly during the period in which this report is
        being prepared;

             b) Designed such internal control over financial reporting, or
        caused such internal control over financial reporting to be designed
        under our supervision, to provide reasonable assurance regarding the
        reliability of financial reporting and the preparation of financial
        statements for external purposes in accordance with generally accepted
        accounting principles;

             c) Evaluated the effectiveness of the Company's disclosure controls
        and procedures and presented in this report our 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) Disclosed in this report any change in the Company's internal
        control over financial reporting that occurred during the Company's
        fourth fiscal quarter that has materially affected, or is reasonably
        likely to materially affect, the Company's internal control over
        financial reporting; and

          5.  The Company's other certifying officer and I have disclosed, based
     on our most recent evaluation of internal control over financial reporting,
     to the Company's auditors and the audit committee of the Company's board of
     directors (or persons performing the equivalent functions):

             a) All significant deficiencies and material weaknesses in the
        design or operation of internal control over financial reporting which
        are reasonably likely to adversely affect the Company's ability to
        record, process, summarize and report financial information; and

             b) Any fraud, whether or not material, that involves management or
        other employees who have a significant role in the Company's internal
        control over financial reporting.

                                                 /s/ WILLIAM C. WELDON
                                          --------------------------------------
                                                    William C. Weldon
                                                 Chief Executive Officer

Date: March 14, 2005