The combined grinding system of "roller press + ball mill" in a cement production line has some problems, such as high power consumption in the process, frequent pressure relief in the roller press and instantaneous stop. By optimizing the parameters of the system process equipment, improving the work efficiency of the roller press, adding the point pressure relief valve of hydraulic system, installing the online laser particle size analyzer, and implementing the transformation of the intelligent control system, the power consumption of the grinding system process is reduced by 2.08kW·h/t, and the standard deviation of cement strength is reduced to below 0.8, which effectively improves the production economic index of the cement grinding system and improves the stability of product quality.