Introduction: synthetic graphite film is a new heat conduction and heat dissipation material with high crystallinity, high grain orientation and low lattice defects, which is made of special polyimide film and high temperature synthesis technology. The in-plane thermal conductivity of synthetic graphite is more than 1500 W / M.K. in practical application, it can improve the heat dissipation efficiency and achieve "heat equalization" effect. Synthetic graphite film is an ideal thermal diffusion material, which has higher transverse thermal conductivity and lower thermal resistance than traditional copper foil and aluminum foil.