Polybenzidine was synthesized by interfacial polymerization under various monomer oxidant molar ratio. Effects of monomer oxidant molar ratio on morphology, structure, and properties of polybenzidine were studied by techniques of Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet Visible Absorption Spectroscopy (UV-vis), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Cyclic Voltammetry (CV). The results showed that all of the samples were microrod-like and the surface of the microrods was smooth and uniform. The changes of monomer oxidant molar ratio had no obvious effect on the morphology of the polybenzidine. The results of structural analysis and cyclic voltammetry indicated that the monomer oxidant molar ratio should not be very high or very low to obtain the polybenzidine with the optimal degree of conjugation, order arrangement of molecular chain, and the best electrochemical behaviors. The suitable proportion in this work was 1:1.