Shihongtan in-situ leachable sandstone-type uranium deposit is one of largest uranium deposits of the interlayer oxidation zone type sandstone-hosted uranium deposits in China. In the course of infiltration and runoff of oxygen- and U-bearing water within the ore-hosting sandstone layers of the deposit, different geochemical subzones such as intensively oxidized subzone, weakly oxidized subzone, reduction subzone and unoxidized primary subzone and their corresponding alteration mineral assemblages are formed due to the difference in properties of aqueous medium when the rock-water reaction happenes. The alteration mineral assemblages in the intensively oxidized subzone are limonite (goethite and esmeraldaite), illite, montmorillonite and a small amount of jarosite, and those in the weakly oxidized subzone are limonite (goethite and esmeraldaite), jarosite, montmorillonite, illite and a small amount of chlorite and kaolinite. The neogenic alteration mineral assemblages in the reduction zone are pitchblende, pyrite, kaolinite, chlorite and a small amount of montmorillonite, I/S clay, illite, carbonate and so on, and those in the unoxidized primary subzone are mainly pyrite, chlorite and kaolinite, with a small amount of carbonate, montmorillonite and illite sometimes.