Energy-saving ball mill changes the intrinsic grinding machine structure. Its body and ground plank are integrated to one unit. So when fixed, it can be lowered on to a basal plane for one time. The use of aligning spherical roller bearing with centripetal spherical support of the main bearing can reduce energy consumption by 30%.The trellis-pattern forced discharging is substituted by the down-flow type controlling so that The milled granularity and the capacity can be increased by 15-20%.