Bismaleamic was selected paper-based test system for the polyimide resin, and a matrix material was modification. The results show that: the material can be modified in the intermediate curing temperature and meet the high-temperature requirements of 360℃. Choosing a lower density sheet metal powder as a conductive filler, and using is bentonite as a composite of polyethylene wax and anti-settling agent, the modified polyimide surface resistance is down to 0. 59 Ω, shielding effectiveness is greater than 40 dB,and the material has good anti-settling properties ,impact resistance and flexibility to meet the requirements of the engine.