Abstract: For development and utilization of valuable element of copper，bismuth，sulfur and iron containing in gravity concentration middlings，which produced by dressing plant of a multi-metal mine，the beneficiation test was carried out on middlings of gravity separation consult on-sile process.The results showed that bismuth concentrate with bismuth grade of 41.59% and bismuth recovery of 29.13%，and copper concentrate with copper grade of 21.03% and copper recovery of 66.31%，and sulfur concentrate with sulfur grade of 42.87 and sulfur recovery of 90.25%，and iron concentrate with iron grade of 68.06% and iron recovery of 21.11% were obtained respectively by the process of Cu-Bi-S bulk flotation，flotation concentrate by gravity concentration using shaking table for bismuth separation，tailing of gravity concentration by inhibiting sulfur for copper flotation，and tailing of bulk flotation by low intensity magnetic separation for iron concentrate.All concentrate products obtained by the mentioned process have good indicator.Therefore，the process tested above is available for the middlings.

Key words: Gravity middlings, Copper-Bismuth-Sulfur, Bulk flotation, Shaking-table concentration, Inhibiting sulfur and floating copper, Low intensity magnetic separation