Located in the Northern Wuyishan district，Jiangxi province，the Gaojiashan copper & molybdic deposits is on the southern of the Pingxiang- Gangfeng fault belt，which is bounded on the north by Yantze plateform and on the south by Huaxia lateform．Previous K-Ar dating studies on Metallogenic Granitoids have shown that the ages were 63.6Ma and 84.7Ma. In this study，precise zircon U-Pb dating was performed on the host granitoids in Gaojiashan deposits. Zircon ages from quartz syenitic porphyry is 232.7±0.6Ma，and dioritic porphyrite which is intrusion of syenitic porphyry or granite-porphyry is 219.6±1.5Ma．Based on the analysis of geochemistic characteristics and stable isotope of δ34S and δ18O，the ore-forming material and fluid was derived from alkali rich magma activity during the Indo-Chinese epoch. So，the result of U-Pb dating also represented the ore- forming age, indirectly. This study indicated that mineralization had happen in this area during the Indo-Chinese epoch.