Located in the southern of Erlian-Hegen mountain belt, Wheercltu is a newly discovered Mo deposit of medium scale in the Erlian-Dongwuqi ore belt of center Inner Mongolia. Molybdenum mineralization consists of quartz-molybdenite veinlets and stockworks which occurs within the Yanshan Period granite stock or along its contact zone with Permian strata. Hydrothermal alteration is well developed and is composed of potassic feldspar alteration, silicification, beresitization、Carbonatation and Chloritization,typical of porphyry Mo deposits.Re-Os dating of 5 molybdenite samples collected from the main ore body shows that the model age is (158.1 ~161.6) Ma and the isochron ages is 158±2Ma (MSWD= 1.16). Re-Os dating and the U-Pb dating indicates that the diagenetic age and mineralization age are close and belong to Middle Jurassic. Thus Wheercltu molybdenum deposit is formed at the early Yanshan period and related to the tectonic - magmatic activities. In consideration of other isotopic age data from the molybdenum deposits in adjacent areas,it can be inferred that magmatism- mineralization of the molybdenum deposit exist more stage in the Erlian Haote-Xilin Haote area, the large-scale porphyry Mo metallogenesis centralized in the Yanshan period.