Sebuta Cu-Mo deposit is located in the north of Gangdese metallogenic belt. It has the characteristics of porphyry copper-molybdenum deposit such as veinlets disseminated mineralization，wall-rock alteration and development etal. This article uses inductively coupled plasma mass spectrometry TJA X-series ICP-MS for the molybdenite Re-Os isotopic dating of granite porphyry in Sebuta， obtained six samples model age is 87.52 ± 1.35～88.8 ± 1.26Ma，and isochron age is 88.8 ± 1. 5 Ma. It shows that the mineralization age of sebuta copper-molybdenum is early Late Cretaceous， and it is the tectonic-magmatic product of Yanshan stage.