Abstract: Closed-circuit test of preferential flotation was made based on the characteristics of refractory copper-sulfur ore form Indonesia.The reasonable process conditions were determined based on the characteristics of the higher copper oxide and soluble copper salt，which solved the problem that a large number of copper in the flotation process is difficult for the copper-sulphur separation.The inhibitors is use of lime and Sodium sulfide，which obtained the copper concentrate of the copper grade is 16.21%，recovery rate is 84.21%，sulfur concentrate of the sulfur grade is 45.14%，recycling rate is 82.11% after the copper-sulfur flotation separation process of cu-preferential flotation and sulphur separation from crude pulp in the condition of the grinding fineness was 75%－0.074mm.