The study of the late Mesozoic granites in South China and its tectonic setting is a hotspot issue. In this study, we report new zircon U- Pb dating, petrogeochemistry, and zircon Lu—Hf isotopic analysis of biotite monzogranites from the Heyuan area, with the aim of determining its age and petrogenesis, important for understanding the late Mesozoic tectonic evolution of the South China Block. Resluts: The Petrography feature suggest that Jingwei pluton mainly consist of biotite monzogranites. Zircon LA- ICP- MS dating results show that biotite monzogranites were formed at the Early Cretaceous (143. 2±1. 3~145. 4±1. 1 Ma). The Jingwei granites is characterized by weak peraluminous and metaluminous, high content of SiO2 (71. 15％~76. 11％), K2O(4. 68％~5. 89％), but low content of Al2O3(12. 58％~14. 03％), depletion in P, Ti, Ba, Sr, and enrichment in Rb, U, Th. The chondrite- normalized patterns of REE are in seagull forms, with strong negative Eu anomalies, with 0. 11 to 0. 26 of δEu, Y/Nb>1. 2, and higher zircon saturation temperatures(791~829℃), which indicates that the Jingwei pluton is similar to A2- type granite. The zircons in the granites have low εHf(t) values (-7. 3~-0. 4) and ancient two- stage Hf model ages (TDM2) (1198~1632 Ma), indicating it has probably formed by partial melting of the predominantly ancient crustal rocks, being mixed with little mantle derived mafic malts, under a low- pressure, high- temperature condition at an extensional tectonic setting, and subsequently the magmas fractionated biotite, plagioclase, K- fedspar, apatite and zircon during emplacement. Conclusion: Combined with regional geological background, we infer that the Jingwei biotite monzogranites was probably related to the roll- back of the subducted Paleo- Pacific plate.