<DOCUMENT>
<TYPE>EX-99.906
<SEQUENCE>5
<FILENAME>ninecert.txt
<DESCRIPTION>906 CERTIFICATION
<TEXT>

         CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT

I,  Donald F.  Crumrine,  Director,  Chairman  of the Board and Chief  Executive
Officer of Flaherty & Crumrine  Preferred Income  Opportunity Fund  Incorporated
(the "Registrant"), certify that:

         1.   The Form N-CSR of the  Registrant  (the  "Report")  fully complies
              with the  requirements of Section 13(a) or 15(d) of the Securities
              Exchange Act of 1934, as amended; and

         2.   The information  contained in the Report fairly  presents,  in all
              material  respects,   the  financial   condition  and  results  of
              operations of the Registrant.


Date:    JANUARY 29, 2004      /s/DONALD F. CRUMRINE
     ------------------------  -------------------------------------------------
                               Donald F. Crumrine, Director, Chairman of the
                               Board and Chief Executive Officer
                               (principal executive officer)


I, Peter C. Stimes,  Chief  Financial and Accounting  Officer,  Vice  President,
Treasurer  &  Assistant  Secretary  of  Flaherty  &  Crumrine  Preferred  Income
Opportunity Fund Incorporated (the "Registrant"), certify that:

         1.   The Form N-CSR of the  Registrant  (the  "Report")  fully complies
              with the  requirements of Section 13(a) or 15(d) of the Securities
              Exchange Act of 1934, as amended; and

         2.   The information  contained in the Report fairly  presents,  in all
              material  respects,   the  financial   condition  and  results  of
              operations of the Registrant.


Date:    JANUARY 29, 2004      /s/PETER C. STIMES
     ------------------------  -------------------------------------------------
                               Peter C. Stimes, Chief Financial and Accounting
                               Officer, Vice President, Treasurer & Assistant
                               Secretary
                               (principal financial officer)


</TEXT>
</DOCUMENT>
