Porphyry Cu-Mo-Au deposits occur not only in an arc setting, but also in a collisional belt. These ore-bearing porphyries in different tectonic settings have distinctly different geochemistry in trace elements, implying that they have different compositions in source or dynamic mechanisms. Comparing with collisional-type ore-bearing porphyries, the subduction-type rocks have obviously high HREE and Y concentrations, low Sr/Y, (La/Yb)N and (Dy/Yb)N ratios, suggesting that their source are mainly consisted of amphibole but less or no garnet. The geochemistry of major and trace elements of ore-bearing porphyric rocks in Pulang-Xuejipin is similar to that of the subduction-type. They are likely the products by partial melting of metasomatized mantle wedge by subduction fluid or sediment, trigged by slab break-off of westward-subduction of Ganzi-Litang Ocean, instead of by direct partial melt of an oceanic slab.