Abstract: With in?depth exploration of natural gas in marine strata in Puguang gas field of Sichuan basin, more and more gas shows are found in its continental strata, of which the member?4reservoir of Xujiahe formation of the Upper Triassic has become the succeeding layer of the major productivity in future in this area. Based on the core, thin?section and well logging data analysis, the characteristics of this reservoir were discussed. Lithology of the reservoir is dominated by lithic sandstone of braided river delta sediment, followed by feldspathiclithic sandstone, and reservoir space is given priority to with secondary intergranular pores, followed by remained primary pores. Compaction and cementation are main factors to destroy the reservoir quality rather than dissolution. The underwater distributary channel and mouth bar are sedimentary microfacies with good reservoir property, next to distributary channel microfacies, which are key targets for next exploration and development in the area