A low-grade refractory copper-nickel sulfide ore in Sichuan contains 0.22 % copper and 0.47 % nickel.The ore contains copper and nickel minerals in fine particles,and it is very difficult to effectively separate copper and nickel.Therefore,direct flotation is adopted to obtain copper-nickel mixed concentrate.The study thoroughly investigated the influence factors such as the grinding fineness,the inhibitor,and the modifier.The results show that when the grinding fineness -74 μm accounts for 70 %,through the flotation process of once roughing,twice scavenging and three times refining,a copper-nickel mixed concentrate with a yield of 5.88 %,a copper grade of 3.31 %,a nickel grade of 5.92 %,a copper recovery of 86.60 % and a nickel recovery of 73.84 % can be obtained.The test indexes of copper-nickel beneficiation are good.