Abstract: In order to improve the output of the cement combined grinding system of the ?4.2m×13.5m ball mill and reduce the power consumption of the system, technical measures were carried out including transforming the cement mill separator, increasing the filtering area of the dust collection system, adding the three-classified separation of the roller press system, adjusting the system process flow and so on. The goals were achieved. The average output of the cement grinding system was increased by 18.83t/h, and the process power consumption was reduced by 4.47kW·h/t.