Abstract:According to traditional tectonic theory, tectonic position of Bilugangan molybdenum deposit in Abagaqiin Inner Mongoliain locates in TianshanInner Mongolia geosynclinal fold system, middle part of late Variscan fold belt, middle part of Abagaqi synclinorium which is the third tectonic unit, and core part of Chagan'aobo overturned anticline. Regional tectonic movements are mainly composed of late Variscan and Indosinian tectonic movements. Triassic intrusive rocksgranite porphyry is closely related with mineralization. Original magma in the deep part of crust intruded in sandy slate and mixed conglomerate rocks, and country rocks have been eroded into all kinds of hornfels eclipse. After differentiation, oreforming materials have been concentrated largely and formed mineralization mother rock after condensation. Host structure will provide favorable space for migration, filling and replacement and mineral precipitation of orebearing hydrothermal. Its mineralization range will be strictly controlled by hydrothermal alteration range. Multiple pulsation of hydrothermal has controlled multistage mineralization of hydrothermal alteration. Superimposed parts are favorable for mineralization and ore enrichment. It is regarded that in the inner and outer contact zone of granitic porphyry and its country rocks, porphyry molybdenum deposit can be formed easily.