The invention relates to a detachable type material discharging screen of a ball mill. The screen is used in the fields of metal and nonmetal mines, chemical engineering, building materials and the like. The screen mainly comprises a material discharging screen frame with a welding structure, T-shaped bolts, a blocking-type screen plate, a residue discharging box, a material discharging barrel liner, an upper material discharging screen cover, a lower material discharging screen cover, a first bolt, a first nut, a first washer, a fourth bolt, a fifth nut, a fourth washer and the like. The inner surface of the material discharging screen frame is connected with the blocking-type screen plate by plural groups of the specially-designed T-shaped bolts, such that the blocking-type screen plate is fixed on the inner surface of the material discharging screen frame. The rear of the material discharging screen frame is fixed with the residue discharging box by standard parts. A front flange of the material discharging screen frame is fixed on the material discharging barrel liner by a standard part, such that the material discharging screen frame is fixed with the ball mill. The upper material discharging screen cover and the lower material discharging screen cover are connected by plural groups of standard parts, and are fixed on the base of the ball mill. The material discharging screen frame is averagely divided into a plurality of equal portions in the circumferential direction by a plurality of pre-cut square holes, and the internal of the material discharging screen frame is welded with a double-head reverse screw. The device of the present invention has characteristics of detachable structure design, good interchangeability and easy disassembly. In addition, the cost is reduced; the service life of the material discharging screen is improved; the material of the screen is changed.