In the light of the knowledge gained by the study of electrochemical flotation for galena and selective flotation of galena from lead-zinc-iron sulfide ores, a technology for accurate potential control based on intrinsic electrochemical behavior in grinding-flotation systems has been developed and is called "Original Potential Flotation (OPF)". The optimum conditions for the Original Potential flotation of galena from the Pb-Zn-Fe sulfide ores were: pH values of 12.5-12.8, potential of 150-180mV and with diethyldithioncarbamate (DDTC) as collector. Lime was used as a regulator of pH, meanwhile, it could stabilize special potential very well, and this special potential was exactly flotation potential of galena. This technology had been applied successfully in potential-control flotation of galena in many complex lead-zinc-iron sulfide mines in China.