Abstract: In northern Qiangtang-Changdu plate of Longmucuo-Shuanghu-Lancangjiang suture zone,the syenitegranite mass of late Permian Epoch is disjointed from the granites of Yanshannia Age.The component of the rocks is characterized by Al₂O₃>CaO+Na₂O+K₂O,with the average value of ASI reaching 1.166,showing the character of typical peraluminous granite;in addition,the ΣREE value of the rock is as high as 466.55×10^-6~2682.80×10^-6,with the average value of of δEu being 0.06,showing the character of typical S-type granites.The rock type is equivalent MPG-granite and is in terpreted as the syncollisional granite.The zircon U-Pb isotope age is 251.4±0.6 Ma,indicating that the implacement age is in late Permian Epoch.All these reflecta tectonic-thermal event during late Permian Epoch to Triassic Epoch,which might be the tectonic outcome of continent-continent collision in Wulan lualake-Lancangjiang suture zone.