Abstract: In order to study the effects of grinding methods on the flotation performance of sphalerite and pyrite,the particle size composition and flotation kinetic parameters of these two minerals under different grinding methods and grinding time were investigated by six flotation kinetic models. The results showed that all the six models can well fitted the flotation test data. The flotation performances of sphalerite and pyrite were determined by oxidation rate,grinding method and particle size composition. Pyrite presented a higher oxidation rate and lower flotation recovery compared with sphalerite. The products obtained from wet grinding were finer than dry grinding. In all tests,the yield of -0. 015 mm size fraction was the highest,which was conducive to the exposure of more new surface and led to the rapid enrichment of pyrite. However,wet grinding accelerated the dissolution of Fe3+ from the grinding medium,which reduced the flotation rate of sphalerite. The dry grinding samples exhibited coarser particle size composition and higher surface roughness,inducing higher ε∞ values of sphalerite and pyrite compared with wet grinding.