The bauxite deposit introduced in this paper is one of the most important bauxite deposit in China. The bauxite consists mainly of diaspore, dickite, kaolinite, chlorite, pyrophyllite, hydromica, Muscovite, mixed-Layer minerals and a few heavy minerals. The diaspore is a main Al-bearing mineral appearing as cryptocrystalline, rnicrogranu-lar, and small-columnar crystals. In mica group, the content of 2M-type muscovite is relatively higher and gydromica is less. The. chlorite is rich-Al dioctahedro-chlorite. The dickite occurs in the bauxites in the form of pisolitie-oolitic aggregate and apparently is an authigenic mineral. The bauxites are chemically characterized by that the content of Al2O3 increases with the content of TiO2, and decreases with the increses in the content of SiO2. The main petrological structures of the bauxites include fragmen-tal. piso-oolitic, laminated, and funnel structures.The mineral association of this deposit is complex. The association closely related with its total chemical composition on the one hand and with physical and chemical conditions on the other hand. The change of minerals is controlled by the process and degree of the diagenetic variation.