Polyaniline film electrode was prepared by constant potential electrolysis. Effects of sweep rate, monomer concentration and temperature on its electrocatalytic performance for polymerization of aniline monomer were studied. Compared with the blank platinum electrode, the potential of the oxidation polymerization of aniline monomer on the polyaniline film electrode shifted negatively. It is showed that the polyaniline film has obvious catalytic action in the polymerization. In addition, the redox peak current on polyaniline film electrode linearly depends on the square root of the potential sweep rate. It is indicated that the electrode reaction on polyaniline film is controlled by diffusion process.