Based on the deeply exploration of Xuequan Copper-zinc deposit in North Qilian Mountain, the book analyzed the typical metallogenic characteristics and metallogenic potential of early Paleozoic Cyprus-VHMS deposits in North Qilian Mountain, presented the view that Cyprus-VHMS is another type of important copper resources except Baiyinchang VHMS deposit, and it can be the important potential replacement resources of Baiyin crisis mine, we should actively carry out the regional investigation. Cyrus-VHMS deposit in North Qilian Mountain formed in middle-late Ordovician (ore-bearing surrounding rock and basalt, the age of zircon U—Pb in gabbro is[ (454±15)～(457.9±1.2)Ma ], the isotopic characteristics of silicon, lead, sulfur, and oxygen indicate that metallogenic materials mainly originate from magmatic fluid of new accreting basaltic series at oceanic crust and oceanic floor, metallogenic tectonic environment is back-arc spreading ridge environment of middle-late Ordovician back-arc basin, metallogenesis is controlled by fracture system in volcanic apparatus, and mainly formed by metallogenic hydrotherm circulation which is eruptive magma fluid mixed with sea water, and the ore-forming elements are mainly copper, crystal-ore in higher grade, associated with zinc, gold, but less lead. The orebody extends longer in vertical than in horizontal, as a result of structural reformation in the later period, the complex shape of orebody increased the difficulty of investigation. The book set up a good example of investigation and exploration for searching for VHMS copper deposit in residual ophiolite of the north Qilian Mountain and other orogenic belts based on the systematic summary of research work into Xuequan Copper (zinc) deposit.