A lot of granitoids exist at Baoertu of Hoxud County in Xinjiang, lying in the middle segment of Middle Tianshan Mountains.Petrologic, mineralogical and geochemical investigations indicate that Wusutonggou pluton, which occurs in northern Baoertu area and belongs to Northern Tianshan Mountains, is composed of a suite of intermediate-acid intrusive rocks showing features of typical calc-alkaline volcanic arc granitoids which are enriched in LILE and depleted in HFSE and have genetic relation with the melting of the lower crust and the assimilation-hybridization of the upper crust resulting from the subduction of the ocean crust. The U-Pb LA-ICP-MS isotope age shows that the Wusutonggou pluton intruded at (358.9±3.5) Ma, belonging to the last stage of Devonian to the early stage of Lower Carboniferous.