Abstract: Based on the study of the property of a complex copper-zinc sulfide ore from tibet, the process flowsheet of preferential flotation Cu and the tailings of flotation Cu treated by flotation Zn was adopted and the technical conditions of Cu-Zn mineral roughing and cleaning were researched.A copper concentrate contenting copper 20.10%with recovery 70.26% and contenting silver 90.20 g/t,  a zinc concentrate contenting zinc 42.33% with  recovery 75.35% and contenting silver 14.80 g/t can be obtained by the finally definitive closed circuit test.Although the copper-zinc separation was successful realized, the recovery of silver in copper,zinc concentrate needs to be further improved.

Key words: Copper-zinc complex sulfide minerals, Preferential flotation, Copper-zinc separation, Combined depressor