Abstract: High operating cost, low efficiency and difficulty in control of quality of flotation concentrate are the challenges facing the flotation system of the plant. To address these problems, an automatic agent dosing and emulsion control system is applied. The system uses the S7-300 PLC as controller, and measures the pulp flow rate and density using respectively electromagnetic flowmeter and densitometer.In this system , after the dosage is calculated by PLC, the agent is dosed using frequency-conversion metering pump while the emulsion of the agent is timely and accurately made by an emulsifier. Practice shows that the use AI-based control software plus digital filtering technology makes it possible to realize reliable storage of measured and calculated data and data curves as well as accurate control of agent consumption.