Abstract: The Rare Earth Elements (REE) resources are rich in China, among which the ion-adsorbed REE deposit in South China is unique. Its spatial and temporal distribution characteristics indicate that its formation is closely related to the Mesozoic granites in South China, but the internal genetic relationship is still not deeply understood. In this paper, a comprehensive study on the Bankeng granite in the Nanling (the ore-forming parent rock of Bankeng REE deposit) has been carried out, including petrography, zircon and apatite chronology, lithogeochemistry, zircon Hf isotopes and whole-rock Sr−Nd−Li isotopes. The U−Pb chronology results of magmatic zircon and magmatic apatite in the Bankeng granites are 185.5~194.0 Ma and 189.2 Ma respectively, indicating that they emplaced occurred in the Early Jurassic. Their mineral composition is mainly composed of felsic minerals (Q+Ab+Or≥95%), with only a small amount of biotite (＜5%) in the mafic dark minerals. Their geochemical characteristics show high SiO₂ (75.93%~77.48%), rich K₂O (5.27%~5.55%), low MgO (0.09%~0.14%), and poor MnO (0.02%~0.03%), as well as a high zircon saturation temperature (801~847℃), high Zr+Nb+Ce+Y content (360×10^-6~534×10^-6), and a 10,000*Ga/Al ratio (3.2~4.2), which are similar with the highly differentiated A-type granites. The Sr−Nd−Hf−Li isotopic characteristics (⁸⁷Sr/⁸⁶Sr_(t)=0.704477~0.712715, ε_Nd(t)= -5.0~-5.2, ε_Hf(t)= -6.8~+1.4, δ⁷Li=-0.88~6.65) indicate that the magma source may be REE-rich igneous rocks from Mesoproterozoic recycled ancient crust that was intruded into the shallow crust. The Bankeng granites exhibits A₂-type granite properties (Y/Nb=1.21~2.09), combined with the regional contemporaneous bimodal intrusive rocks, volcanic rock suites and A-type granitoids, indicating they formed in the early Jurassic extensional tectonic setting. Combined with the genetic understanding of A-type granite in the Nanling at the same time as Bankeng granites, this paper suggests that the thermal anomaly generated by the upwelling of deep asthenosphere in the early Jurassic caused partial melting of REE-rich rocks in the crust-mantle magmatic source area to form more REE-enriched A-type granitic melt, which may be one of the important mechanisms for the petrogenesis of ore-forming parent rocks of the ion-adsorbed light REE deposits in South China. The genetic correlation between the LREE-riched Bankeng granites and the HREE-riched Zudong granites shows that the petrogenesis of the LREE-type ore-forming parent rocks is mainly related to their magma source region and extensional tectonic setting, while the degree of magma crystallization differentiation and the external fluid metasomatism are more critical for the petrogenesis of the HREE-type ore-forming parent rocks.