A high-resistant one was selected from several silicone resins. There was no absorption peak in the spectrum of 300 nm to 3000 nm according to the transmittance of the film material from 185 nm to 10⁴ nm.The refractive indexes and extinction coefficients in the wavelengths of 600 nm to 1600nm were deduced by the method of Manifacier,which were 1.513 and 0.0006 at 650 nm,respectively(at 26℃) and would decreased to 1.512 and 1.489 after exposed to UV for two hours. Polarization dependence wasn't detected by laser-V-prism device. The scattering loss of the film was less than 0.5 dB/cm based on the analysis of the surface characteristic with an RMS roughness of 1.7 nm and transmission loss. These results proved that this silicone resin could be valuable in the making of waveguide devices used in plastic optic fiber communication system.