PURPOSE: To stick and arrange a uniform and secure diamond layer on the surface part of the steel plate by laminating powder mixture layers, composed of Ni powder and diamond powder and acid-soluble steel sheets on the surfaces of the steel plate, then hot rolling the steel plate to dissolve the acid-soluble steel sheets and projecting the diamond.

CONSTITUTION: The powder mixtures 2, 12 composed of the Ni powder and the diamond powder are laid on the respective surfaces of carbon steels 1, 11 and the acid- soluble carbon steel sheets 3, 13 are joined thereon. These steel sheets are so laminated via a release agent 4 to allow easy releasing in such a manner that the steel sheets 3, 13 face each other. Metallic plates 5, 15 are tightly adhered to the four peripheral side faces of this laminate to enclose these side faces to prevent the splashing of the powder mixtures 2, 12 and the release agent 4. The laminate is then hot-rolled. The metallic plates 5, 15 are removed after the end of the hot rolling and the laminated plates for two sheets are separated. The separated plates are immersed into a hot hydrochloric acid soln. to dissolve the steel sheet 3, 13 parts to form the state in which the diamond powder 6 projects uniformly on the surface layer part. The diamond clad steel plate press-welded and arranged with the diamond uniformly and securely in the wide area on the surface of the steel plates 1, 11 is obtd. in this way.