The newly discovered Xiarihamu and Shitongkende magmatic nickel- cobalt sulfide deposits in the East Kunlun orogenic belt (EKOB), China are associated with cobalt resources. The cobalt mineralization of these magmatic Ni- Co deposits, combined with different types of independent cobalt deposits such as hydrothermal and sedimentary deposits found in the EKOB, were related to early Paleozoic mafic magmatism to varying degrees. These illustrate the huge metallogenic potential of early Paleozoic mafic magmatism in the EKOB. The Xiarihamu super- scale Ni- Co sulfide deposit has become a typical deposit of Ni- Co large- scale magmatic mineralization in the orogenic settings. Based on the screened existing rock geochemical data, this paper determines the variation characteristics of Co, Ni and Cu etc. metallogenic elements in different lithofacies, and discusses the mafic magmatic cobalt enrichment mechanism and controlling factors. The mafic- ultramafic rocks in the Xiarihamu deposit show higher cobalt contents that varies greatly with different locations (magmatic period), rock and mineral types. The cobalt content is rich in peridotite and pyroxenite facies rocks with high MgO contents. The cobalt content in sulfide ore is the highest. The cobalt content in different types of rocks is positively correlated with the sulfur, nickel and copper content. These results indicated that the Xiarihamu magmas were enriched in Co, and sulfide melt is the main mechanism of cobalt enrichment. The mechanism of cobalt enrichment in minerals during magmatic evolution requires systematic understanding of cobalt occurrence at the atomic level.