Abstract: An exploratory study is made on the optimum design of the flotation agent addition automatic control system,with an aim to enhancing the efficiency and accuracy of the system. Based on the study result,a froth image analyzer and an expert data system are incorporated into the traditional automatic control system used in most cases. The optimum design of the system has led to much improved control performance and,hence,reduced consumption of flotation agent. The study made is conductive to the further development of the automatic control system.