The modification of the non-linear conductivity property for polyimide by the non-linear filler was studied.The conductance property and other dielectric properties of pre and post modification and the influence of the amount of non-linear filler for conductance property of polyimide was also investigated.The experimental results indicate that the conductivity of the modified composite materials varied according to the amount of non-linear filler.When the mass fraction is less than 5%,the conductivity declined slightly,when the mass fraction is more than 5%,the conductivity went up significantly.The non-linear conductivity of modified composite materials changed obviously.