The East Qinling area is the largest molybdenum metallogenic belt in the world, as well as the most important molybdenum ore-concentrated area in China. The Dashigou deposit is one of the typical carbonatite-type molybdenum deposits in East Qinling area. Molybdenum mineralization is the main mineralization in Dashigou deposit, accompanied by uranium, rare earth, lead and other metal mineralization. Previous studies have paid more attention to molybdenum and rare earth mineralization in this deposit, but only few have researched uranium mineralization. In this study, typical uranium mineralization samples were selected to conduct TIMA, scanning electron microscopy, electron probe microanalyzer and laser ablation inductively coupled plasma mass spectrometry for identifying petrographical, geochemical features of minerals and isotopic geochemical research. The results show that the main uranium minerals of uranium mineralization in Dashigou deposit are brannerite, uraninite and betafite. The uraninite is characterized by high Y, Ce and low Si, Ti, Na and Mg. The U/Th, ΣREE, LREE/HREE of the uraninite indicate a magmatic origin, which formed in high temperature, high salinity and relatively reducing environment. The uraninite EPMA U-Th-PbTotal chemical dating and LA-ICP-MS in-situ U-Pb dating result show the uranium mineralization epoch is ～223 Ma (late Triassic), which indicated that the uranium mineralization in the Dashigou carbonatite was formed in the post-orogenic extensional environment of the Qinling Orogenic Belt during the Indosinian. Based on previous studies and this paper, it is concluded that the uranium mineralization epoch of the Dashigou deposit is consistent with the main carbonatite molybdenum deposit in the Qinling Orogenic Belt. As products of magmatic activity in the same period, the uranium mineralization and molybdenum mineralization may have formed in the same geological event.