Exhibit 31.2

                    CERTIFICATION OF CHIEF FINANCIAL OFFICER

In connection with the filing of the Quarterly Report on Form 10-Q for the
quarter ended September 30, 2003 by Kirby Corporation, Norman W. Nolen,
Executive Vice President, Treasurer and Chief Financial Officer, certifies that:

         1.   I have reviewed this quarterly report on Form 10-Q of Kirby
              Corporation (the "Company");

         2.   Based on my knowledge, this quarterly 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 quarterly
              report;

         3.   Based on my knowledge, the financial statements, and other
              financial information included in this quarterly 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 quarterly 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(d) and 15d-15(e)) for the
              Company and we 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 quarterly report
                   is being prepared;

              b)   Evaluated the effectiveness of the Company's disclosure
                   controls and procedures and presented in this quarterly
                   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

              c)   Disclosed in this quarterly report any change in the
                   Company's internal control over financial reporting that
                   occurred during the Company's most recent 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:

              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

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              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/ NORMAN W. NOLEN
                                       -----------------------------------
                                       Norman W. Nolen
                                       Executive Vice President, Treasurer
                                          and Chief Financial Officer

Dated: November 11, 2003

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