The Shi-Hang zone is an important NE-SW-trending Mesozoic magmatic belt inSouth China,which is dominated by granites with relativelyhigh εNd(t)values andyoung TDM model ages.Here,we present laser ablation inductively coupled plasmamass spectrometry(LA-ICP-MS)zircon U–Pb ages,major and trace elementcompositions,and Sr-Nd-Hf isotope data for the Yuanzhuding porphyritic granitoidswithin the southwestern Shi-Hang zone,and use these data to determine the origin ofthis granitoid and its relationship with Cu–Mo mineralization.Zircon U–Pb datingindicates that these granitoids were emplaced at 157.8±1.1Ma. They have initial87Sr/86Sr ratios of 0.70941-0.71398,εNd(t) values of -3.15 to -2.02, and in situ zirconεHf(t) values of +1.71 to +6.17.Geochemically,most of them are high-K calc-alkalineand show an adakitic affinity.They are more likely to emplace in a continental arcsetting related to westward subduction of the palaeo-Pacific plate. Their parentalmagmaoriginated chiefly from the overlying sediments of the downgoing slab,andsubsequently interacted withthe lithospheric mantle wedge at the temperatures of～790℃.High oxygen fugacity during magmatic evolution played a crucial role in thedevelopment of Cu–Mo mineralization within the Yuanzhuding.The discovery of theYuanzhuding deposit implies that theChenzhou–Huaiji fault belt is most likely prospective for mineral exploration for porphyry Cu–Mo deposits.