Zircon SHRIMP dating was performed to study Yunmengshan gneissic granite and, as a result, four groups of zircon ages were obtained, namely,144±4 Ma, 160～163 Ma, 193～218 Ma and 2 416 Ma. The age of 144±4 Ma represents the emplacement age of Yunmengshan gneissic granites, and can serve as new important evidence for the emplacement of Yunmengshan gneissic granite. The two age groups of 160～163 Ma and 193～218 Ma probably represent the ages of zircon captured during the emplacement of magma. The age of the inherited zircon is about 2 416 Ma, identical with the zircon U-Pb upper-intercept ages by Davis (1996). This suggests that Yunmengshan gneissic granite was probably derived from partial melting of late Archean gneiss or that late Archean zircon was captured during magmatic intrusion.