Abstract: Aiming at the difficulted Separation of zinc leach residue of some smelter which obtained by High-temperature and high-acid leaching zinc process，the paper researched the existing state of the material composition and silver of the leaching Zinc slag and the assemble collector and the modifier affect on silver flotation. The results showed that undering the best pharmacy system of mmonium dibutyl dithiophosphate and B sulfur nitrogen （2:1） as assemble collector 800 g/t 、（NaO₃P）₆ 600 g/t、Na₂S 800g/t ，the optimized open circuit test can get the silver grade of concentrate is 2 301 g/t ， the recovery is 57.29%，which compared to the don’t optimized open circuit test（40.05%） the recovery is increased 17.24%. Adopting one fast floating，one roughing stage，two cleaning stages and two scavenging stages of the closed circuit process can obtain one concentrate with silver grade is 3 087g/t， recovery is 5.67% ， and another silver concentrate with silver grade is 2 186g/t，recovery is 61.23% ，realized silver recovery.