Abstract: The Taoxihu tin-polymetallic deposit, located in the southwestern section of Lianhuashan fault belt in the eastern area of Guangdong Province, is a medium-sized hydrothermal vein-type Sn-Pb-Zn deposit in Jiexi County. The study focused on granite porphyry closely related to mineralization so as to sysmatically analyze ore-forming source and tempo-spatial relationship of this deposit. Geochemical, S isotope and Hf isotope analysis results show that the granite porphyry provided ore-forming materials for the deposit. LA-ICP-MS zircon U-Pb age of granite porphyry is 141.8±1.0 Ma. Re-Os isochron age of molybdenite associated with cassiterite and arsenopyrite is 139.0±1.1 Ma, which is almost the same age as that of granite porphyry. Combined with the geological features of the mining area, granite porphyry is inferred as the most important metallogenic parent rock in the Taoxihu tin-polymetallic deposit.