Abstract: A lead-zinc sulfide ore from Sichuan is a low-grade,high-calcium refractory ore,with lead and zinc grades of 1. 41% and 8. 12%,Respectively;Lead and zinc mainly occur as sulfides. Due to the low lead grade and high content of calcium-bearing gangue minerals,conventional flotation cannot achieve effective separation and recovery of lead and zinc. To achieve efficient development and utilization of this ore,flotation separation tests were carried out. A preferential flotation process was adopted,with self-developed YTH as the collector and zinc sulfate and sodium sulfite as combined depressants. The process flowsheet and reagent regime were determined through flotation condition tests. The results showed that a full-process closedcircuit test using the flowsheet of " preferential lead flotation and zinc flotation from lead flotation tailings",in which both lead and zinc flotation adopted one roughing,one scavenging,and three cleaning stages,yielded a lead concentrate with a lead grade of 63. 57%,a lead recovery of 75. 52%,and a calcium content of 0. 19%,as well as a zinc concentrate with a zinc grade of 57. 37%,a zinc recovery of 73. 62%,and a calcium content of 0. 74%. This process achieved the effective development and utilization of low-grade,high-calcium lead-zinc sulfide ore and can provide guidance for the industrial production of similar ores.