A CNC turning, milling, grinding and engraving universal machine tool, which is composed of a machine bed, a machine tool spindle box, a turning chuck, a turning tool holder, a carriage gearbox in the turning of the machine tool, a tailstock of the machine tool, and a CNC universal indexing Head, hydraulic coupling, engraving milling machine column, cylindrical grinding head, engraving and milling electric spindle, engraving and milling square ram and external grinding square ram. Its characteristics are: on the basis of a pair of guide rails on the ordinary lathe bed, a pair of column guide rails for engraving, milling and grinding machine tools is added, a turning pin spindle box is set on the machine tool bed, a hydraulic coupling is set on the left side, and a CNC universal dividing head is set on the right. There are two square rams on the side of the turning pin tool holder and the tailstock of the machine tool, and the column of the engraving, milling and grinding machine: one is the outer round grinding square ram, the front end of which is equipped with an outer round grinding head and the grinding head motor, and the rear end is equipped with a ball Lead screw and servo motor, the second is engraving and milling square ram, its front end is equipped with up and down walking servo motor, ball screw, electric spindle, and its rear end is equipped with ball screw and servo motor. Realize multiple processing operations such as car sales, indexing, grinding, milling and engraving.