Abstract: The Taolegai Gold Deposit is a newly discovered large-scale quartz vein-altered rock type gold deposit in the Ulate Rear Banner, Inner Mongolia. The ore body was formed in Carboniferous quartz diorite and was controlled by two sets of faults: NWW-trending and NNW-trending. The hydrothermal mineralization in the mining area was divided into four mineralization stages: disseminated pyrite−quartz stage（Ⅰ）, quartz−pyrite（± galena ± chalcopyrite） stage（Ⅱ）, quartz（± chalcopyrite ± pyrite）−galena−sphalerite stage（Ⅲ）, and quartz−calcite stage（Ⅳ）. The gold mineralization in the mining area was closely related to Permian biotite plagioclase granite and was genetically classified as a mesothermal magmatic hydrothermal deposit. This work focused on using 3DMine software to conduct 3D spatial modeling of the NWW-trending No. 7 and No. 9 ore veins in the mining area. The results show that the better mineralized parts of No. 7 ore vein are mainly concentrated in the range of Exploration Line 23–Exploration Line 15 and Exploration Line 7–Exploration Line 0, with mineralization exhibiting characteristics of lateral subduction to the west at a medium angle in the horizontal direction and segmented enrichment in the vertical direction. The better mineralized parts of No. 9 ore vein are located between Exploration Line 11–Exploration Line 3 and Exploration Line 15–Exploration Line 4, respectively, with mineralization enrichment also exhibiting characteristics of lateral subduction to the west at a medium angle in the horizontal direction and segmented enrichment in the vertical direction. Both are controlled by the right-lateral thrust movement of the NWW-trending ore-controlling fault during the mineralization period. Based on the above rules, six deep prospecting target areas for further exploration of No. 7 and No. 9 ore veins have been delineated.