Abstract: The study on the diversity of Arbuscular Mycorrhizal Fungi in northern Tibetan plateau plant showed: the arbuscular mycorrhizal fungi of plants in Tibet altiplano pasture distribute widely, 4 genera arbuscular mycorrhizal fungi was isolated totally. Among them, the Glomus is the widest distribution and dominant genera; the Acaulospora is the second wide distribution, while the Paraglomus and Scutellospora are the common generas. In different grassland type, the diversity of arbuscular mycorrhizal fungi in alpine grassland is more than it is in alpine meadow. The paraglomus mainly distributed in alpine meadow pasture but the scutellospora has no distribution in this area and the diversity of arbuscular mycorrhizal fungi coincide with the position of host plant in northern Tibetan plateau. Altitude not only negatively correlated with spore density (r = –0.478), but also significantly effected the ecological distribution of arbuscular mycorrhizal fungi. Within different soil PH range, the species frequency of Glomus significantly increased with soil PH increasing, and the species frequency of Scutellospora have neutral> alkaline tendency, Paraglomus only distributed in neutral soil environment, the diversity of arbuscular mycorrhizal fungi in low phosphate soil environment lower than which in high phosphate soil environment.