By using the Cathode fluorescence image analyse and LA-ICP-MS U-Pb age dating method of zircons，the inner structure, trace element compositions and U-Pb age of the zircons of pyroxene syenite and fine potash-feldspar-granite in the form of vein in the complex body of Mazhaertage located in the northwest of central uplift in Tarim basin are analyzed and determined. The results of zircon analysis show that the diagenesis ages of two types of rock are 283.3±1.8Ma and 281.2±3.7Ma separately, these dates open out that there is the activity of alkaline magma during early Permian period in the north of Tarim basin, and provide the important evidence of mantle plume magmatism and direction of research related to mineral exploration about diamond, oil and gas from the Carboniferous to Permian period .