The coating after nanocomposite has excellent electromagnetic properties. The coating formed by nanoparticle coating has good wave absorption ability and can be used for stealth coating. Nano titanium oxide, chromium oxide, iron oxide and zinc oxide and other particles with semiconductor properties are added to the resin to form a coating with good electrostatic shielding performance; 80nm barium titanate can be used as a high dielectric insulation coating, and 40nm ferrosoferric oxide can be used for magnetic coating; nanostructured multilayer film system produces giant magnetoresistance effect and is expected to be used as a read head in storage system.