Abstract: In order to improve copper and molybdenum separation efficiency,the copper and molybdenum separation process in Duobaoshan Copper(Molybdenum) Mine is renovated and the reagent regime is optimized based on small-scale test and flowsheet investigation,during which the roughing scavenging flowsheet shifts to twice roughing and once scavenging from once roughing and twice scavenging,and the collector shifts from kerosene to kerosene＋used oil.Industrial production shows that after renovation molybdenum grade is 45.939 % and copper grade is 1.862 % in molybdenum concentrate;copper grade is 20.830 % and molybdenum grade is 0.143 % in copper concentrate;for copper and molybdenum separation operation,molybdenum recovery rate is increased to around 85 %,and comprehensive molybdenum recovery rate exceeds 70 %,10 percentage points higher than that(59.60 %) before the renovation,living up to the idea of “recover as early as possible” for mineral processing operation;in the meantime,used oil is recovered and reused,saving mineral processing cost and increasing economic profits.