The aim of this work was to improve the mechanical properties of polypyrrole, PPy, by its electropolymerization onto a cast film of poly[bis(phenoxyphosphazene)], PBPP, in order to form a PBPP–PPy composite, with NaClO 4 as electrolyte and acetonitrile as solvent. The influence of the electrosynthesis method (galvanostatic or potentiostatic) on the polymerization efficiency and specific charge storage capacity was studied. The presence of PBPP increased the polymerization efficiency and decreased the specific charge storage capacity for composites generated potentiostatically, but its influence was less marked for composites obtained galvanostatically. With both methods the incorporation of PBPP improved the mechanical properties, but the electrochemical stability decreased. The effects of current density, thickness of PBPP and electropolymerization time were studied. The specific charge storage capacity increased with PBPP thickness. The composite was studied by Fourier transform infrared (FTIR). In the high frequency region the FTIR spectra showed the absorption tail characteristic of conducting polymers in both PPy and in the composites. In the low frequency region, bands attributed to PPy, PBPP and ClO 4 − were analyzed in order to confirm the electrochemical results.