In this article, we report the geochemical, zircon U- Pb dating, and Hf isotope data from granite porphyry in the Dushugou gold deposit, Tanjianshan area, in the North Qaidam. Bulk- rock analyses show that this intrusion is characterized by the enrichment in silica(SiO2=75. 23%~77. 28%), sodium (Na2O/K2O=1. 71~2. 41), and depletion in iron (TFe2O3=1. 04%~3. 24%), magnesium (MgO=0. 28%~0. 39%), calcium (CaO=0. 23%~0. 75%), and aluminum (Al2O3=13. 09%~13. 73%). The rocks are enriched in large- ion lithophile elements, such as Rb, Th, U, and K, and depleted in the high- field- strength elements, such as Nb, Ta, Ti and P. The rocks are enriched in light rare earth elements relative to heavy rare earth elements, and have obvious negative Eu anomaly ( δ Eu=0. 49~0. 53). Furthermore, the differentiation index (DI) of the Dushugou granite porphyry ranges between 90. 76 to 93. 71, which is the characteristic of strong crystallization differentiation. Based on the comparison of the characteristics with the adjacent granite, we propose that the Dushugou granite porphyry is highly differentiated I- type granite.Zircon U- Pb dating of the Dushugou granite porphyry yields magmatic crystallization ages of 350. 8±1. 7Ma, with the εHf( t ) values ranging from +1. 82 to +9. 19, with an average value of +6. 85, and a two- stage Hf model age ( t DM2) range from 1238 to 768Ma. The variation range of Hf isotopic composition of the Dushugou granite porphyry is large, suggesting that the material composition of its source area is relatively complex.The magma source was dominated by Neoproterozoic juvenile accreted crustal materials, mixed with Mesoproterozoic and even older crustal materials.Based on the Paleozoic tectonic evolution history of the Northern Qaidam, it is concluded that the Dushugou granitic porphyry was formed in the extensional environment after collisional orogeny in Early Paleozoic.