Tight sandstone gas far from source rocks in the Shaximiao Formation of the Jurassic system is one of the key areas for oil and gas exploration in the Sichuan Basin. The natural gas charging capacity under the control of fault-sand configuration controls the scale of natural gas accumulation and enrichment in the Shaximiao Formation. However, there is still a lack of quantitative evaluation of the selective charging capacity of natural gas to different sand bodies. Taking the central Sichuan Basin as an example, based on the analysis of the characteristics and sources of natural gas reservoirs and the source-fault-sand configuration relationship and its evolution, a quantitative evaluation of natural gas charging was carried out, and the gas charging capacity of tight sandstone in the Shaximiao Formation was determined. The results show that the tight sandstone gas in the Shaximiao Formation in the central Sichuan Basin mainly comes from the source rocks of the Xujiahe Formation. There are significant differences in the natural gas charging capacity of different river sand bodies in the Shaximiao Formation. Among them, the charging capacity of the No. 8 sand formation in the east of the Longquanshan Fault is the largest, followed by the No. 8 sand formation in the south of the Jiao① Fault, which plays a decisive role in the natural gas accumulation and enrichment of the Shaximiao Formation. Comprehensive analysis suggests that the efficient matching of source-fault-sand is the key to the accumulation of tight sandstone gas far from source rocks. The source-fault configuration controls the scale of natural gas sources, and the fault-sand configuration determines the effectiveness of natural gas charging. This study quantitatively reveals the mechanism of natural gas accumulation and enrichment in the Shaximiao Formation in the central Sichuan Basin, which is significant for the exploration and development of tight sandstone gas far from source rocks.