Abstract: Shunzuo granite is located in the Wuzhishan area of Hainan Island, on the east and west sides of the Cretaceous volcanic rocks. The LA-ICP-MS zircon U-Pb dating yielded an age of 254.4±2.4 Ma, suggesting Late Permian. Petrology and geochemistry show that it belongs to the sub-alkaline rock series, with SiO₂ content 69.88%~74.51%, 72.99% on average, implying an acidic rock. It has obvious negative anomalies of Ba, Ta-Nb, P and Ti and obvious positive anomalies of Rb, K, Pb and Nd. The initial strontium ratio is 0.70947~0.717388, which is lower than the average ratio of strontium to continental rock (0.719), suggesting moderate strontium granite. ε_Nd(t) is-9.25~-5.14, and T_2DM is 1444~1777Ma. It might have resulted from the action of crust thickening in the deep melts and NW-SE trending extrusion on slate, phyllite, plagiogneiss, granulite, plagioclase diopside and other rocks or deeper similar rocks, being a product of stress synergy. It is S-type granite, and the emplacement is a strong emplacement type in the syn-collision structure environment. It is of the hot air balloon expansive type underplating. It belongs to the shell source remelting granite, which was formed in the syn-collision environment.