Abstract: A lead-zinc sulfide mine in Sichuan has low lead-zinc grades and high sulfur content.Some galena and sphalerites in the ore have finer grain sizes,vein-like and disseminated inlays,which affect the separation indexes of lead-zinc flotation.Under the existing separation process,the zinc content in the lead concentrate is relatively high,which affects the zinc recovery rate.For this reason,on the basis of the research of process mineralogy,an experimental study on the optimization of the lead flotation process was carried out.25# areofloat was used as the lead collector in the new process and the lead coarse concentrate is reground to reduce the zinc content in the lead concentrate,improve the lead grade of the lead concentrate and the zinc recovery rate of the zinc concentrate.Under the conditions of 1.21% of lead,2.19% of zinc and 25.48 g/t of silver in the raw ores,lead concentrate with lead grade of 45.58%,zinc contents of 5.43%,silver contents of 861.72 g/t and lead recovery rate of 84.11%,and zinc concentrate with lead contents of 1.11%,zinc grade of 54.10%,and zinc recovery rate of 87.14% could be obtained.The grades of lead concentrate and zinc concentrate were increased by 2.42 and 3.72 percentage points compared with the on-site process,respectively,and the lead and zinc recovery rates were increased by 0.26 and 4.11 percentage points respectively,which provides guidance for the actual production of the lead-zinc ore.