Objectives: Xueru pluton is an important indicator to discuss the regional development and evolution of Bangong Lake—Nujiang River metallogenic belt in Ban’ge area. It is essential to carry out geochronological, LuHf isotope study and petrogeochemical analysis for better understanding of the porphyritic monzonitic granite. Methods: On the basis of detailed field work, the petrogeochemical testing and LAICPMS zircon UPb dating age are carried out on the porphyritic monzonitic granite. Results: LAICPMS zircon UPb age 78.59±0.55 Ma (MSWD=0.96), belongs to the interim of the Late Cretaceous and is basically consistent with the diagenesis age obtained by predecessors. Petrogeochemical researches indicate that the granite belongs to highK calcalkaline, and is peraluminous granite with A/CNK=1.03~1.04. The granite is enriched in Th, U, Zr, Hf and LREE, depleted in Nb, P, Ti and HREE, with medium negative Eu anomly (δEu=0.71~0.73). The value of zircon εHf(t)is -10.05~0.37, and the mean value is -3.34. Petrogechemical analysis shows that the granite has the characteristics of Itype granite. Its source rock is continental crust and it is from partial melting. Conclusions: Comprehensive studies indicate that the granite formed in the syncollision background, which represents the collision event between Qiangtang block and Lhasa block after the closure of Bangong Lake—Nujiang River ocean.