Datuanshan XI # 2 orebody at shizishan copper mine is a deep large size orebody,mined by the sub level open stoping method.According to some disadvantages of the mining method designed originally in the practical operation,some improvements of stope slotting,stope bottom structure and production blasting have been made to decrease the quantity of development and opening work and the ratio of large fragments,so that the daily ore removal of stope is increased greatly.