A rectifying heterojunction consisting of polyparaphenylene(PPP) and polypyrrole(PPY) films was prepared by the electrochemical method. The photoresponse in the heterojunction of PPY and PPP is similar to the absorption spectrum of undoped PPP. This fact suggests that photoresponse depends strongly upon polyparaphenylene of semiconductor. The fill-factor was calculated from the photo current-voltage curve to be 0.19, which is relatively small compared to polyacetylene-polythiophene heterojunctions.