Abstract: In order to rationally develop a Pb-Zn-Au-Ag complex polymetallic ore in Qinghai Prov⁃ ince，a detailed beneficiation test was carried out on the polymetallic ore. The test results show that the effective separation of lead，zinc and sulfur is realized by using the process of preferential separation of leadzinc- sulfur mixed flotation-zinc-sulfur separation when the raw ore was ground to -0.074 mm 65%. A lead concentrate with lead content of 73.62%，zinc content of 1.89% and lead recovery rate of 77.01%，a sulfur concentrate with sulfur grade of 35.47%，lead content of 1.34%，zinc content of 0.73% and sulfur recovery rate of 2.84%，and a zinc concentrate with zinc content of 44.20%，lead content of 1.21% and zinc recovery rate of 87.30% were obtained by a small closed-circuit test in the laboratory. The resource utilization rate was greatly improved and the economic benefit was remarkable.

Key words: lead-zinc ore, grinding, preferential flotation, lead and zinc separation, zinc and sulfur separation