Abstract:The Linjiang Cu deposit, located in Changbai country, Jilin Province, is a typical skarn deposit. On the basis of previous studies, a study of LA-ICP-MS zircon U-Pb dating analysis is performed on quartz diorite-porphyrite in order to restrain its metallogenic epoch. The ages obtained can be subdivided into two groups. The first group contains two zircons with ₂₀₆Pb/₂₃₈U 128.7±2.8Ma and 131.4±3.78Ma, belong to captured detrital zircons. The second group contains 16 zircons, with weighted mean ₂₀₆Pb/₂₃₈U age of 122.6±1.1Ma(n=16,MSWD=0.80), which was interpreted to be the crystallization age of quartz diorite-porphyrite. Combining with zircon characteristics and the genetic type of ore deposit, indicate that this deposit mineralization occurred in early Cretaceous. Combining with regional tectonic evolution, we assume that the Linjiang Cu deposit formed in the subduction of the Pacific Plate beneath Eurasia.