Abstract: The Youshan-Maotouzai rock body, located in the South Jiangxi-North Guangdong area, is an important part of the Dayu Mountains and a representative granite pluton in the Nanling region. However, studies of its geological features, petrogenic chronology, tectonic and metallogenic specialization are relatively few. In this study, based on detailed field research, Laser Ablation-Multicollector Inductively Coupled Plasma-Mass Spectrometry (LA-MC-ICP-MS) was used to detect the formation age of the Youshan-Maotouzai complex. The test results show two peak ages for the magmatism of the Youshan pluton, 236.5 Ma and 437.8 Ma, which indicate that the Youshan rock body is a complex pluton and is mainly formed by the two magmatic events of the Caledonian period and the Indo-Sinian period, but not the Yanshanian period, as the previous study suggested.