The invention discloses an enamelled diamond mold of a high-speed large round wire horizontal enameling machine, and relates to the field of high-speed large round wire horizontal enamelling machine painting processes. Diamond is processed to form a mold core, nickel, zinc, cobalt, molybdenum, copper, tungsten and tin are mixed and stirred to obtain a mixed raw material, the mixed raw material and a grinding aid are added into a ball mill for ball milling to obtain sintered powder, a mold holder is fixed by a graphite mold sleeve, the mold core is placed in the mold holder, then the sintered powder is added between the mold holder and the mold core for sintering processing, the mold core is fixed to the center of the mold holder through hot pressing sintering by a powder metallurgy process, and the mold is obtained. According to the mold, the diamond mold core is arranged, the diamond mold core has the advantages of being good in stability, not prone to number shifting, long in service life and the like, a diamond mold core body is connected with the mold holder through a sintering body, the sintering body has high tensile strength, the diamond and the mold sleeve are welded into a whole, the situation that the mold core is stable can be effectively ensured, and gap paint leakage is permanently rejected.