Abstract: In order to provide basis for exploitation and utilization of a low grade copper-nickel sulfide ore from Yunnan province，mineralogy and relevant mineral processing experiments on this ore was conducted.The results showed that：①The valuable elements of the ore are mainly copper and nickel，valuable minerals are mainly chalcopyrite，nicopyrite，violarite and nickel-bearing pyrrhotite.Copper and nickel mainly exist in the form of their sulfide，accounting for 84.09% and 85.96% separately，and copper and nickel are closely associated with each other and difficult to separate.Bulk flotation will be suitable to recover copper and nickel；②The optimal grinding fineness was 80% passing 200 mesh，and Na2CO₃，CMC，CuSO₄,and butyl-xanthate+thiamine ester were used as pH modifier，inhibitor of gangue minerals，activator for copper and nickel minerals，and collectors separately with corresponding proper dosage for bulk flotation of 800 g/t，400 g/t，200 g/t and 90+30 g/t；③Copper and nickel mixed concentrate with copper grade and recovery of 6.02% and 83.05%，nickel grade and recovery of 3.97% and 84.55% separately was achieved through process of one roughing，three scavenging，concentrate-scavenging for firstly scaveng concentrate，one cleaning for mixed concentrates of scaveng concentrate and rough concentrate，and middles back to the flowsheet in turn.

Key words: Copper-nickel sulfide mine, Close intergrowth, Bulk floatation