The Hongshan complex is an important component of the Mesozoic intrusive rocks in the North Taihang Mountain, and is especially significant in alkaline rocks. We firstly report the porphyry Cu mineralization from the Hongshan complex in the southern Taihang Mountains and carried out a comprehensive research.Methods:In this paper, zircon U Pb dating, petrogeochemical investigation and zircon Hf isotope analysis of the ore bearing syenite porphyry are studied to constrain its geochronology and petrogenesis.Results:LA ICP MS zircon U Pb choronology indicates that the porphyry was emplaced at 130.45~131.4Ma, slightly older than the Hongshan syenite (132~135Ma) and the formation of the Han Xing type iron skarn deposits (133~137Ma). It shows the Hongshan ore bearing syenite porphyry was emplaced in the summit of magma activity in the region of Taihang Mountains and formed in the timing of large scale lithospheric thinning in North China Block. The syenite porphyry is silica rich (SiO2=63.72%~67.63%), potassium rich (K2O/Na2O=0.73~1.36) and alkali rich (K2O+Na2O=12.34%~12.73%), belonging to shoshonitic series, with the characteristics of LREE enrichment, HREE depletion, and no Eu anomaly (δEu=0.93~1.05). The syenite porphyry is enriched in LILEs such as Rb、Th、U、K, etc, and delepted in HFSEs such as Nb、Ta、Ti, etc. 24 analyses from two samples of the ore bearing syenite porphyry give a wide range zircon εHf（t）values (-24.4~-10.3) and varying Hf isotope crustal model ages (1.6~2.7Ga). Conclusions:All of the above datas imply that the magma originated from partial melting of the EMI type mantle source which was contaminated by crustal materials in the process of magmatic upwelling to form a potassium rich ore bearing magma with mixed sources of the crust and the mantle.