Abstract: Using three kinds of sulfur-containing iron ore with different sulfur content and single mineral of pyrite as samples, the effects of grinding fineness, grinding medium and subsequent aeration on the distribution of reagents in the ore flotation process were studied.The results show that grinding with steel rod medium, the distribution rate of xanthate on the surface of ore is low, which is not conducive to the adsorption of xanthate on its surface.When using porcelain ball as grinding medium, the distribution of xanthate on the surface of the ore is high, which is beneficial to the adsorption of xanthate on its surface.Aeration is favorable to the adsorption of xanthate by ore, which can increase the distribution rate of xanthate on the surface of ore.However, after grinding with porcelain ball medium, the effect of aeration on the adsorption of xanthate on ore is small.Grinding medium has little effect on the adsorption of xanthate by single mineral of pyrite.