Polypyrrole (PPY) prepared in ether and in aqueous medium has been modified by polycondensation with phthalic anhydride (PA) and pyromellitic dianhydride (PMDA) in presence of Friedel-Crafts catalysts such as anhydrous zinc chloride and anhydrous ferric chloride at high temperature. The substitution reaction between PPY and the anhydrides presumably proceeds by intra- and interchain processes resulting in the formation of intractable products. The characteristic carbonyl absorption band expected for C-O and diketone groups in the proposed structure for the polycondensates has been observed in the spectra of the anhydride-modified poly-condensates. XRD pattern of the polycondensates is totally amorphous.