The gabbrodiabases are exposed along the Jinsha River from Gongbo, Zhongmo t o Zhongxinrong, Derong County, Western Sichuan Province. UPb dating of zircons f rom the Gongbo gabbro has yielded a lower intercept age of 448±7 Ma, and an up per intercept age of 1821±81 Ma. On the concordia diagram, all data points are close to the lower intercept, and among 7 analyses, one zircon gives a concordan t age of 478±7 Ma. It is suggested a Caledonian Continental rifting event in re lation to early evolution of the Jinshajiang PaleoTethyan oceanic basin.