The Gangdese metallogenic belt (GMB) in Tibet, located within the East Tethys metallogenic domain, is one of the most famous Pb, Zn, and other nonferrous metal areas in China. A notable discovery in recent years is the Pusangguo deposit, which is rich in cobalt and contains Cu–Pb–Zn ores. The ore bodies mainly occur within the contact zone between the magma and the Early Cretaceous Takena Formation strata, displaying a complex mineralization pattern. Within the Pushangguo deposit, sphalerite is one of the main sulfides in the quartz-sulfides mineralization stage. Notably, there are two distinct types of sphalerite: dark-brown type I sphalerite (SpI) and light-brown type II sphalerite (SpII). This paper employs electron microprobe analysis (EMPA) and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) to analyze the trace elements present in sphalerites. The results show that sphalerite is generally rich in Co, with SpI exhibiting a higher Co content than SpII. Co mainly replaces Zn (Co2+→Zn2+) through isomorphism. Both SpI and SpII showcase enrichment of Fe, Mn, and Cd, as well as depletion of Ga, Ge, and In. The occurrence of Fe, Mn, Cd, and other elements is mainly in the form of isomorphism, while Cu, Ag, Pb, and As appear as mineral inclusions within sphalerite. Based on the observed correlation between different trace elements, it is proposed that there exist potential simple complex element substitution mechanisms. These mechanisms include Fe2++Mn2+→2Zn2+, (In3+, Sn3+)+(Cu+, Ag+)→2Zn2+, As3++Ag+→2Zn2+, and Pb2++2As3++□→4Zn2+ (where □ represents a lattice vacancy). Furthermore, the ratios of Fe, Mn, Ge, In/Ga, In/Ge, and Zn/Cd in sphalerite, along with the calculations based on the sphalerite GGIMPis geothermometer, indicate that sphalerite was formed in an environment of medium-high temperature (237~345℃), low oxygen fugacity, and low sulfur fugacity (logf(S2)=-13.4~-8.3).