Porphyry Cu deposits constitute the world’s major source of Cu, and have been major research and exploration target for a long time. Since the new century, not only mineral exploration but research level has made new breakthroughs or significant progress. So far proven porphyry Cu ore reserves are 1.8 billion tons, and mainly distributed over the western continental margins of North and South America, South-west Pacific, Central Asian countries, and Tethyan realm (include Eastern Europe segment, Iran-Pakistan segment, Tibetan areas in China), of which the western continental margins of South America contain 1.1 billion tons of Cu ore reserves. Proven porphyry Cu ore reserves decreased along with the formation era from the Cenozoic, Mesozoic, Late Paleozoic, and Early Paleozoic to the Precambrian. Porphyry Cu deposits predominantly located in upper part of the ocean subduction zone where the porphyry Cu-Au deposits formed in island arc, and porphyry Cu-Mo or Cu-Au-Mo deposits formed in continental margin. The subduction angle variation of slab from steep to gentle, even slab, is responsible for the formation of the porphyry Cu deposits; formation of giant deposits is spatially associated with the flat slab subduction of aseismic ridges, seamounts and oceanic plateau. The transform faults distributed in oceanic plate are easily replaced by seawater, of which these subducted faults beneath continent or island arc are favorable for the formation of ore-forming magma; and the conjunction sit of different continental geotectonic parts, where subducted slab became weak and susceptible to tear, is also an important place of formation of the metallogenic belt. The partial melting of the asthenosphere mantle wedge, which had undergone metasomatism induced by the subduction fluid, has been considered to be main forming process of the arc magma, since the subducted slab carries abundant seawater and seafloor sediments into the asthenosphere. The basic magma with high oxidation extent and rich volatile experienced the MASH and differentiation process in the lower crust, gradually evolved into intermediate-acidic ore-forming magma with light specific weight, ascend to the shallow depths along fault belts and finally formed deposits. The studies of continental porphyry Cu deposits are attracting more attention in the last 10 years, and ore-forming materials derived from the crust-mantle interaction of continental interiors (include juvenile lower crust) or the metasomatic lithosphere originated from remelting of residual subducted slab has been cast in the spotlight. The studies of deposit models from the single mineralized alteration model to the deposits combined model are still the emphasis from the perspective of mineral exploration. In addition, geologists carried out research in the Footprint (indicator for deposit) depending on altered minerals of porphyry Cu deposits system (eg. chlorite, epidote, alunite and clay minerals), discussed the distribution law of orebodies, and further proposed the indicator for deposits.