CERTIFICATION PURSUANT TO RULE 30A-2(B) UNDER THE 1940 ACT AND 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 27, 2006            /S/ DONALD F. CRUMRINE
     ----------------------          -------------------------------------------
                                     Donald F. Crumrine, Director, Chairman
                                     of the Board and Chief Executive Officer
                                     (principal executive officer)

I, R. Eric Chadwick,  Chief Financial  Officer,  Treasurer and Vice President 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 27, 2006            /S/ R. ERIC CHADWICK
     ----------------------          -------------------------------------------
                                     R. Eric Chadwick, Chief Financial Officer,
                                     Treasurer and Vice President
                                     (principal financial officer)