Abstract: By means of core observation,thin section analysis,physical property analysis and scanning electron microscope(SEM)techniques,the study on influencing factors of petrology characteristics,diagenesis,reserving space and reservoir physical properties has been carried out.The results indicate the lithology of the upper Triassic hydrocarbon reservoir is mainly of feldspar lithic sandstone,debris arkose,feldspar sandstone and lithic sandstone,the compositional and textural maturity is in medium degree,and the reservoir pores are mainly of the intergranular solution pores and particles dissolved pores in secondary pores.The physical properties are generally poor,the reservoirs are obviously controlled by sedimentary micro-facies,and the underwater distributary channel is the most favorable facies in this area.