Abstract: In order to solve the technical problem of low copper recovery efficiency in the flotation process of complex high-sulfur copper-zinc ore，a high-sulfur copper-zinc ore in Yunnan is taken as the research object，and the synergistic flotation comparison test of ammonium butyl aerofloat，mercaptobenzo⁃ thiazole sodium（MBT-Na）and its composite system is systematically carried out. The synergistic effect and flotation performance under different collector ratios are discussed.The experimental results show that when the mass ratio of MBT-Na to ammonium butyl aerofloat is 2.5，the composite system exhibits the best synergistic collection effect.On this basis，zinc sulfate，lime and water glass are used as inhibitors，2# oil is used as foaming agent，and the closed-circuit process of one roughing，three cleaning and three scav⁃ enging is adopted. Finally，the excellent indexes of copper concentrate grade of 32.54% and copper recov⁃ ery of 95.24% are obtained，and the efficient recovery of copper in the high-sulfur copper-zinc ore is real⁃ ized.It provides theoretical basis and process guidance for the efficient flotation of complex high-sulfur cop⁃ per-zinc ore and the optimization of collector system，and is of great significance to promote the efficient utilization of polymetallic ore resources and the development of green beneficiation technology.

Key words: high-sulfur copper-zinc ore, synergistic flotation, ammonium butyl aerofloat, mercapto? benzothiazole sodium