Based on the analyses of sedimentary facies, cast thin slices, rock and mineral logging data, the diagenesis of the sandstones in different tectonic zones of Xujiahe Formation have been researched systematically. The conclusion shows that in the thrusting nappe tectonic zone, there are mainly compaction and cataclasis. Based on the research of diagenesis, the diagenetic facies is divided, and the diagenetic facies association of Xujiahe Formation sandstone is divided into three types, the diagenetic facies which is beneficial to the reservoir development are compaction-clastation-cementation and cementation-denudation types.