The PI/SiOZ/A1Z03 nanoparticles hybrid films with mass fraction rang from 1%to 5% had beensynthesized using the situ polymerization preparation method. Through scanning electron microscope(SEM)testingmeans，it was found that the inorganic A1Z03 nanoparticles and SiOZ nanoparticles have good compatibility and dis-persion in the polyimide matrix，and the size of A1Z03 nanoparticles and SiOZnanoparticles are about 100 nm. Theeffects of different doping concentrations on the mechanical and electrical properties of PI film were researched byuniversal testing machine and broadband dielectric spectroscopy analyzer. When the doping mass fraction was 3 %，the mechanical property of the hybrid film is optimal，and has a maximum tensile strength(36. 143 MPa)and