PDC for oil drill bits series is produced by using the higher degree of diamond power and tungsten carbide substrate through adopting advancing international technology. Microstructure with complete C-C bond combination is characterized between the grains of the diamond in polycrystalline diamond layer, which allows the high strength, hardness and wearing property of diamond layer. We adopt many types of claw structure of the interface between diamond layer and tungsten carbide substrate, and use the special technological late conditions in order to effectively reduce residual stress of PDC while make the interface combination firmer and more symmetrical. So applied to oil drill bits, PDC displays satisfying thermal stability, higher impact resistance and excellent performance.