Catalytic activity of conducting polymers in biofuel cells has been studied in comparison with the performance of Pt-black (Pt-B). The cells were direct and passive type with structure of biofuel/anode catalyst/Nafion®/cathode catalyst/air. Conducting polymers of polyaniline, polypyrrole and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT*PSS) were examined for the anode and cathode catalysts. L-ascorbic acid was used as the biofuel, and the Nafion® was served as a proton transfer membrane. In the standard Pt-B anode/Pt-B cathode cell, the typical Voc (open circuit voltage) = 0.52 V, ISC (short circuit current) = 8 mA/cm2 and the Pmax (maximum power density) of approximately 0.8 mW/cm2 were obtained. In a cell with catalysts of PEDOT*PSS anode/Pt-B cathode, Voc = 0.55 V and the maximum power density of 1.2 mW/cm2 were obtained, which were larger than that of the standard Pt-B/Pt-B cell. Polyaniline and Polypyrrole were also found to be a potential candidate for catalysts in biofuel cells.