Abstract: Qichun Liemazui molybdenum mine in Hubei Province is located on the southern slope of Dabie Mountain. Proven large molybdenum mines are rarely reported. There are few in−depth studies on this mining area, and there is a lack of accurate determination of the diagenetic and mineralization age, genesis and tectonic setting. In this paper, the Liemazui ore−forming granite was selected for petrographic, and petrochemical studies. The experimental results indicate that the ore−forming rocks are porphyry monzogranite or monzogranite−porphyry by petrographic analysis. The ore−forming scale of the mining area is small. The ore is disseminated or veined disseminated. The isochronous age of molybdenite in liemazui deposit is 119±8 Ma, the weighted mean age was 118.9±0.98 Ma. Therefore, the Liemazui molybdenum deposit is formed in the Early Cretaceous. Geochemical data show that it is a high−silicon, high−potassium, calc−alkaline series A−type granite. The total amount of rare earth elements is high, the light rare earth elements are enriched, and the heavy rare earth elements are relatively deficient. The rocks related to metallogenic formation in the Liemazui molybdenum mining area were formed in the extensional environment of the Dabie orogenic belt, and were related to the thinning of the lithosphere in the Late Yanshanian period.