In the Liuhuanggou area, There are lots of residues of oil&gas-asphalt and bleaching of sandstone that widely spread in the uranium occurrences. In order to find out their spatial and temporal distribution and genetic relationship, Fluid inclusion and organic geochemistry of asphalt sandstone ore bodies have been investigated. Fluid inclusions in the ore-hosting sandstone under microscope are composed mostly of liquid hydrocarbon inclusions and hydrocarbon-bearing brine inclusions, with minor gas hydrocarbon inclusions. The homogenization temperature of the hydrocarbon fluid mainly changes from 60℃ to 90℃, and the salinity mainly varies from 0% to 8% , indicating a kind of medium-low temperature and salinity fluid. Acidolysis hydrocarbon test demonstrated that ore-hosting sandstone have experienced one medium to weak rapidly hydrocarbon-charging. Gas chromatography-mass spectrometry shows that the peak carbon number of n-alkanes in organic matter is C14~C25, with the single peak stype, suggesting that the main soureces of organic matter is algae. Odd-even predominance index(OEP) and carbon preference index(CPI) are 0.474~1.58, 0.887~2.7 respectively, displaying that the organic matter have different maturity. The ratio of pristine to phytane(Pr/Ph) varies from 0.40 to 1.43, mainly under 1, indicating a deoxidization environment for the organic matter. Pr/nC17, Ph/nC18 is 0.164~0.833, 0.595~1.54 respectively, and the bulge shape of convex baseline in the total ion current figure is not obvious, which indicate that oil and gas endured slight microbial degradation. Base on the relationship between the reduction of hydrocarbon and uranium mineralization, and combined with field geological characteristics, The authors hold that oil and gas in the area have two function: firstly, It protect and hide the early uranium deposit. secondly, It further improve the reduction ability of the sandstone layers, thus provide the reducing agent for late uranium mineralization.