Abstract:Meixian in Guangdong Province, is located in the Lianhuashan fault zone, southern part of Zhenghe-Dapu fault zone. The 1:50 000 field geological survey and indoor analyses have indicated the existence of Late Mesozoic extensional structure system in the Meixian of Guangdong Province. This system consists of detachment fault and two stripper layers with different levels. Based on contact relationship and high-precise dating data of volcanic rocks, intrusive rocks and sedimentary rocks, we concluded that the time scale of this extensional structure system ranges from Late Jurassic to Early Cretaceous (160-135 Ma), with the peak time of extension around 145 Ma. Lianhuashan fault zone was previously believed to be formed around the early Paleozoic, and now it is confirmed to be a detachment fault formed at the Late Jurassic. So the Zhenghe-Dapu fault extensional system also occurred in the Late Mesozoic. The results above showed that the dominant tectonic activity in the southern China occurred in the Mesozoic, providing a new reference model for the study of regional metallogenic rules of hydrothermal metal deposit in the southern China.