Abstract: The diamond layer of polycrystalline diamond (PCD) composite was grinded by a diamond flat grinding disc at high speed. The change of the removal rate of polycrystalline diamond material and the surface quality (surface roughness, surface morphology) of the specimen were analyzed by changing the pressure during grinding. The results show that the increase of grinding pressure will improve the material removal rate of polycrystalline diamond, reduce the surface roughness, increase the surface smooth area, and reduce the pits and gap cracks.