Abstract: Polyaniline were synthesized in various dispersant systems by chemical oxidative polymeri zation, using aniline as monomer and ammonium persulfate as oxidant. Its structure, conductivity, particle size distribution and electrochemical properties were measured by laser particle size analyzer, Fourier transform infrared spectrum, four point probe resistance instrument and electrochemical workstation. Results show that all dispersants can reduce its particle size distribution and improve its conductivity and electrochemical stability. In the condition of polyethylene glycol 400 as dispersant and the mass content of 20% in aniline monomer, average particle size of the synthesized polyaniline is 3.85 μm, its electrical conductivity is 4.68 S/cm and polarization potential is 0.73 V.