Shapinggou porphyry molybdenum deposit is now the largest Mo deposit in China, it was discovered recently in the western Dabie Mountains, along the east extension of the famous Qinling Mo mineralization belt. The ore body is mainly hosted in high-K granitic porphyry reclusive undground and fewer exposed outcrop in quartz syenite, with characteristic explosive breccia, potassic alteration and beresitization, molybdenum closely associated with explosive breccia during outcrop observation and drilling analysis. The geochemical data indicate granitic porphyry is characterized by felsic, sub-alkaline, high K2O, low Na2O and Ca2O. Molybdenite analyses yield a Re-Os isochron age of 111.1±1.2 Ma for the deposit. Zircon U-Pb ages are 111.5±1.7 Ma and 111.6±1.9 Ma for the granitic porphyry and quartz syenite, respectively. There are two different types of zircon from granitic porphyry, some of them are hydrothermal zircons with typical CL photos related with molybdenum mineralization, others are igneous zircons hardly asscoatied with mineralization. Hydrothermal zircons have higher Y/Ho and Ce4+/Ce3+ out of classical“CHARAC”field. Shapinggou pure Mo deposit is different from Cu(Mo) deposit with lower oxygen fugacity controlled by Ce4+/Ce3+ and (Eu/Eu*)N from zircon. The Ti-in-zircon temperatures are 860 C and 830 C for the quartz syenite and granitic porphyry, respectively. Similar to the majority of deposits in the Qinling Mo belt, it is located in a backarc setting, to the north of the Triassic suture between the North and South China Blocks. We propose that asthenosphere upwelling induced by slab roll back of the subducted Pacific plate formed high temperature quartz syenite, which led to partial melting of metamorphosed Mo-rich sediments on its way up, resulting in large scale mineralization.