A new method of fabricating Ti layer on diamond surface was proposed to obtain the metallization of diamond surface. A Ti bar heated to a certain temperature with induction method was rotated, extruded and rubbed on the surface of shielded polycrystalline diamond. The surface temperature of polycrystalline diamond was measured with infrared thermometer. The interface and inner surface of Ti layer, and the interface between polycrystalline diamond and cemented carbide were observed with scanning electron microscope. The phase composition of the inner surface, the elements of the interface and inner surface of Ti layer were analyzed with X-ray diffractometer and energy spectrum analyzer, respectively. The research results show that the mutual diffusion of C and Ti elements occurs at the interface between polycrystalline diamond and Ti layer, and TiC with spot shape is generated. The chemical bonding between polycrystalline diamond and Ti layer can be realized. Thermal damage at the interface between polycrystalline diamond and the cemented carbide can be effectively avoided by placing polycrystalline diamond in an electromagnetic shielding device. The formation process of Ti layer on diamond surface can be divided into three stages: contact of fresh surfaces, initial diffusion and formation of diffusion band. The proposed method has features of fabricating processes simply, increasing layer efficiency significantly and avoiding diamond thermal damage effectively.