The East Qinling molybdenum ore belt is located on the southern margin of North China plate, and the distribution of molybdenum ore deposits are controlled by the NW—NWW trending GushiLuanchuan deep fault zone.The Huangshuian Mo (Pb) deposit is defined to one of the carbonatite veintype by the authors in this paper, thus we have one more example of this type in addition to the existing diposits as Dashigou, Shijawan and Taoyuan etc.in the Huanglongpu area.The molybdenum metal reserves of the ore belt occupies the first place for a singular molybdenum ore belt known in the world. Moreover, the coexistence of the oreforming system for carbonatite veins and that for graniteporphyry is an important characteristic different from other molybdenum ore belts. The results of the study show that the carbonatite veintype Mo (Pb) deposits of Huangshuian and Huanglongpu have δ13C values ranging from-5.3‰ to-7.0‰ and 87Sr/86Sr ratios ranging from 0.7049 to 0.7065. At the same time, the calcites are enriched in light REE(LREE/HREE ratios vary from 1.8∶1 to 2.9∶1). Moybdenit is characterized by high Re content (average value ranging from 110 to 244 ppm). Based on the diagrams showing 87Sr/86Sr vs. 206Pb/204Pb, 207Pb/204Pb vs. 206Pb/204Pb and 143Nd/144Nd vs. 87Sr/86Sr of calcites from the orebearing carbonatite veins, the authors consider that EMI might exist below the continental crust in the region of the ore belt, and these orebearing carbonatite veins are crystalfractionational products of alkaline silicatecarbonate meltsolution originated from the EMI, and molybdenum and lead as oreforming metals should come mainly from EMI. In consideration of the oreforming ages of Huangshuian and Huanglongpu (Dashigou) Mo (Pb) deposits (ReOs ages are 209.5Ma and 221Ma, respectively ), the carbonatite veintype Mo (Pb) deposits should be formed in the extension stage of late Triassic which is postcollisional orogenesis of the North China and Yangzi plates, while the porphyryand porphyryskarntype Mo deposits should be formed in late Jurassicearly Cretacous (ReOs ages ranging from 147Ma to 116Ma) which is also an extension stage after Jurassic intracontinental orogenesis.