Polymethylsilane (PMS) is made up of backbone of -Si-Si-, which is potentially a semi-conducting or conducting polymer after doping. Different phenolic groups are introduced into the main chain through Si-H substitution reaction. The polymer structures, optical properties and conducting performance are characterized. The aromatic modified PMS show a significant red-shift in UV absorption and fluorescent emission, higher oxidation resistance in the air and better film-forming properties. The conductivity values are about 10(-6) S cm(-1) and reach as high as 10(-5) S cm(-1) after I-2-doping. At the same time, they also keep a good solubility in several organic solvents. The effect of functional groups in improving optical and conductive performance is studied, and the relationship between crosslink structure and oxidation resistance is discussed.