Glow discharge polymerization among such reactive functional silanes as 3-methacryloxypropyltrimethoxysilane (MSL), 3-glycidoxypropyltrimethoxysilane (ESL), and vinyltrimethoxysilane (VSL) on poly (methyl methacrylate) was investigated by means of Fourier transform infrared spectroscopy, ESCA analysis, and contact angle measurement. Flow rate of monomer influenced both polymer deposition rate and polymer elemental composition. Infrared spectra showed differences in chemical structure among the polymers prepared from the different silanes.