Exhibit 31.2

                               CERTIFICATION

I, Randy C. Martin, Executive Vice President - Corporate Development and
Chief Financial Officer of Spartech Corporation, certify that:


1.   I have reviewed this quarterly report on Form 10-Q of Spartech
     Corporation;

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 statement 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 quarterly report, fairly present in all
     material respects the financial condition, results of operations and
     cash flows of the registrant as of, and for, the period presented in
     this report;

4.   The registrant'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 15d-15(e)) for the
     registrant 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
          registrant, 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 registrant'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

     c)   Disclosed in this report any change in the registrant's internal
          control over financial reporting that occurred during the
          registrant's most recent fiscal quarter (the registrant's fourth
          fiscal quarter in the case of an annual report) that has
          materially affected, or is reasonably likely to materially
          affect, the registrant's internal control over financial
          reporting; and

5.   The registrant's other certifying officer and I have disclosed, based
     on our most recent evaluation of internal control over financial
     reporting, to the registrant's auditors and the audit committee of the
     registrant'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 registrant'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 registrant's
          internal control or financial reporting.

March 11, 2005                        By: /s/Randy C. Martin
   (Date)                                 Randy C. Martin
                                          Executive Vice President -
                                          Corporate Development and
                                          Chief Financial Officer
                                          Spartech Corporation