Rencha basin is one of the typical Mesozoic-Cenozoic volcanic fault basins in northeastern Guangdong. The borehole data indicate that the basement is mainly composed of Paleozoic metamorphic rocks and Wenxiang granite. At present, the basement granite has been lacking in precise years. In order to discuss its formation age and improve the understanding of the geological evolution of the area, LA-ICP-MS zircon U-Pb isotopic dating of Wenxiang granite cores from two boreholes in the Chagan area of the basin is carried out, and the two harmonic ages are 179+1 Ma and 186 Ma, respectively. The results show that the basement Wenxiang granite in Rencha Basin was formed in late Early Jurassic, which is the product of the first volcanic activity of Yanshan. This age not only deepens the understanding of the formation and evolution of Rencha Basin, but also provides new chronological data for the lack of magmatic activity in the Early Jurassic in northeastern Guangdong, China.