The porphyry-type molybdenum deposit in east Gobi is the first oversize molybdenum deposit in Xinjiang. Being different than a typical porphyry-type molybdenum deposit, the orebody is not located in the internal or external contact zone of porphyry bodies, but is situated in the veins of surrounding rock outside the porphyry body. The veins related with mineralization primarily consist of quartz veins, potassium feldspar veins, and some other polygenic veins. The author also believes that the hydrothermal ore-forming solution mainly originated from porphyritic granite magma. The results of study are intrusive and can be used for reference to the further discussion of methods and process of magmatic hydrothermal mineralization.