Abstract: In order to investigate the effect of the novel collector KMC-1 on the separation of copper and molybdenum from a copper-molybdenum ore, the different kinds of collectors including butyl xanthate, AP, Y89 (C₆H₁₃OSSNa), isoamyl xanthate, ammonium butyl aerofloat and KMC-1 were compared through flotation tests and screening-hydraulic analysis. The results showed that the novel collector KMC-1 was better than the other five collectors. Using the flowsheet of “Cu-Mo bulk flotation–Cu-Mo separation” and KMC-1, the molybdenum concentrate with the yield of 0.021%, molybdenum grade of 47.79% and molybdenum recovery of 89.14% was obtained, as well as the copper concentrate with the yield of 1.85%, copper grade of 29.87% and copper recovery of 91.23%. Furthermore, the molybdenum concentrate contained 0.51% copper, and the copper concentrate contained 0.021% molybdenum, demonstrating that the mutual content of copper and molybdenum in the respective concentrate was low, and the separation of copper and molybdenum was realized. Additionally, copper minerals and molybdenum minerals in the coarse-grained range could be efficiently collected with KMC-1, resulting in higher grades of copper and molybdenum in concentrate.