Shixi lithium deposit is located in the eastern limb of the Shixi syncline, Tongzi County, Guizhou Province. For the first time, the abnormal enrichment and mineralization of lithium element in the Lower Permian Dazhuyuan Formation was found outside the Wu (chuan), Zheng ('an) and Dao (Zhen) areas of northern Guizhou. Hosting in the middle and upper parts of the Dazhuyuan Formation, the lithium enrichment layer is characterized by stable thickness and lithium grade. The lithium- bearing bauxite layer mainly composes of illite (hydromuscovite), with massive and clastic structures. Based on mineralogical, petrological and geochemical study, it is concluded that the enrichment of lithium in the Shixi area is related with the ancient weathering and leaching processes, and is controlled by multiple factors during the bauxitization, such as paleoclimate, palaeogeomorphology and palaeohydrology. According to the geochemical composition of the Dazuyuan Formation in the Wu—Zheng—Dao and Shixi areas, variation of Li content has an obvious correlation with Al2O3 content and Al/Si ratio, and is linked with the lithological variations. Moderate Li enrichment is found in mudstone or aluminous mudstone, high grade bauxite; while the high Li enrichment is found in bauxitic claystone and low- grade bauxite. Based on the discovery of the Shixi lithium deposit and comprehensive analysis, it is considered that there is high potential to find high- grade bauxite- type lithium deposit in the nearshore plain environment, especially in palaeokastic depression areas.