According to the characteristics of the ore, a new type of quaternary ammonium salt collector Y28 was used in the desilication of high sulfur and high silicon bauxite ore in Guizhou province. The content of Al2O3 is 55.69%, the content of SiO2 is 14.27%, Al/Si ratio is 3.90, the content of sulfur is 1.71%, silica-bearing minerals kaolinite and muscovite. The experiment of desulphurization and desilication was carried out by using reverse flotation process, the Al2O3 recovery is 54.07%, Al2O3 grade is 62.04%, Al/Si ratio is 6.29, sulfur content is 0.32%, it has met the requirements of the national standard four-grade bauxite.