Abstract:Based on the background of grinding classification system of Xinli concentrator in Sanshandao Gold Mine, the technological process characteristics of the system are analyzed and studied. According to the characteristics of the production process,based on the original basic automation and the actual production, a set of automatic control system for grinding classification has been developed and applied in the concentrator［1］. The application results show that the control system ensures the overflow granularity of the hydrocyclone and improves the efficiency of grinding and classification.