Located in northern margin of the Dayaoshan uplift and Fengkai County of Guangdong-Guangxi boundary，Cu-Mo mineralization of the Yuanzhuding porphyry deposit commonly exists within the Yuanzhuding adamellite porphyry and its outside contact zone. Asteroidal pyrite，chalcopyrite and molybdenite can be found within the porphyry body，but industrial Cu-Mo orebodies mainly lay in the outside contact zone and distribute as ellipsoids encircling the porphyry body: molybdenum mineralization→copper-molybdenum mineralization→copper mineralization compliably appears from the porphyry body outwards，which shows that the Cu-Mo mineralization is closely related to the adamellite-porphyry. The authors carried out with high decision SHRIMP zircon U-Pb and Re-Os dating technique chronological study of the adamellite-porphyry and orebodies，gained 154±2Ma（95% confidence，MSWD=0.75，N=11）of zircon U-Pb age and 155±5Ma（95% confidence，MSWD=0.31，N=8）of molybdenite Re-Os isochron age，respectively，which shows that diagenetic mineralization of the Yuanzhuding Cu-Mo orefield happened during the Late Jurassic period. According to the ages，the authors concluded that the porphyry and mineralization were formed in an extension geotectonic setting in South China.