Abstract: The Zhahe pluton is located in the north part of the Sanjiang Orogenic Belt, with NW trend, which is controlled by NE direction fault. According to the detailed survey, the obtained zircon U-Pb ages of quartz diorite and tonalite are (190.4±2.8) Ma and (192.1±1.2) Ma, respectively, indicating that the Zhahe pluton was formed in Early Jurassic. The dating result suggests that the Jinshajiang suture zone was affected by the tectonic-magmatic activity in this period. On the chondrite-normalized REE diagram, this pluton is enriched in LREE and has a flat HREE pattern. The slight negative anomaly of Eu indicates that this pluton experienced a fractional crystallization of plagioclase. The trace element distribution of this pluton is similar to the ones of island arc magma.Based on the geochemistry and petrography characteristics mentioned above, it's concluded that the Zhahe Pluton has affected by the subduction component and it might be formed in a tectonic compression island arc or active continental margin.After analyzing the field geological survey and regional tectonic evolution, it's believed that the north part of Sanjiang Orogenic Belt had entered the stage of intracontinental convergence in Early Jurassic Period, and that this tectono-magmatic event has affected by the northwardsubduction of Bangong Lake-Nujiang Ocean and serves as the product of this sustained tectonic effect.