Abstract:The Gangdese metallogenic belt (GMB) in Tibet, located in the East Tethys metallogenic domain, is one of the famous Pb, Zn and other nonferrous metal areas in China. The Pusangguo is a large newly discovered cobalt- rich Cu- Pb- Zn deposit in recent years. The ore bodies mainly occurred in the contact zone between the magma and the Early Cretaceous Takena Formation strata, with the complex mineralization. Sphalerite is one of the main sulfides in the quartz- sulfides mineralization stage in the Pushangguo deposit. It mainly contains two different types: dark- brown type I sphalerite (SpI) and light- brown type II sphalerite (SpII). In this paper, the electron microprobe analysis (EMPA) and laser ablation inductively coupled plasma mass spectrometer (LA- ICP- MS) were used to analyze the major and trace elements in sphalerites. The results show that the sphalerite is generally rich in Co, and the content of Co in SpI is obviously higher than that in SpII. Co mainly replaces Zn element (Co) in the form of isomorphism Co2+ Zn2+; Both SpI and SpII are characterized by enrichment of Fe, Mn, Cd and depletion of Ga, Ge, In, among which Fe, Mn, Cd and other elements occur mainly in the form of isomorphism, while Cu, Ag, Pb, As and other elements occur mainly in sphalerite in the form of mineral inclusions. According to the correlation between different trace elements, it is considered that there may be Fe2++Mn2+→2Zn2+、(In3+, Sn3+)+(Cu+, Ag+)→2Zn2+、As3++Ag+→2Zn2+、Pb2++2As3++□→4Zn2+ (□is lattice vacancy) and other simple complex element substitution mechanisms. The ratios of Fe, Mn, Ge, In/Ga, In/Ge, Zn/Cd in sphalerite and the calculation results based on the sphalerite GGIMPis geothermometer indicate that sphalerite was formed in the environment of medium- high temperature (237~345℃), low oxygen fugacity and low sulfur fugacity (lgfS2=13. 4~8. 3).