Abstract: The overflow rate of the flotation feed desliming pond was originally under manual control-a control made with low accuracy and lagging trouble. In the light of the specific operating conditions,a technical renovation scheme is worked out and put into practice. Practice shows that the application of the automated control system can meet the specific requirement of the flotation circuit for its capability to maintain higher stability of overflow rate of desliming pond,give full scope to sizing and desliming effects,and keep the overflow rate of desliming pond and flotation feed pump flowrate well balanced.