Abstract: Geochemical characteristics (including major elements，minor elements and chemical speciation of uranium) of a sandstone uranium deposit from Xinjiang and their effects to in-situ leaching of uranium have been analyzed.The active uranium in the chemical speciation of uranium is principal，with low proportion of the inert uranium.Effects of contents of SiO2 and Na2O and LOI (loss on ignition) on uranium concentration of leaching solution are relatively large，but that of the distribution of minor elements are light.Chemical speciation of uranium is a decisive influencing factor for leaching rate of uranium.The higher content of active uranium is，the higher leaching rate of uranium will be in general，and vice versa.Hence，the sandstone uranium deposit can be exploited suitably by using the technique of in-situ leaching with dilute sulfuric acid after integrated considering the distribution characteristics of major elements and the chemical speciation of uranium.

Key words: Geochemical characteristic, Chemical speciation of uranium, In-situ leaching of uranium, Sandstone uranium deposit