Abstract: Arbuscular mycorrhizal fungi (AMF) are beneficial microorganisms, distributed widely in many different soil types. The investigation of species diversity of AMF in extreme environments is a rapidly developing area of research because of the potential benefits for ecosystem restoration. Screening for effective arbuscular mycorrhizal fungi species is regarded as an important approach to successful revegetation. The identification of arbuscular mycorrhizal species and their distribution were investigated in 15 natural saline-alkaline Leymus chinensis grasslands in 12 regions of the western Songnen Plain. The occurrence frequency, species richness and spore density were also investigated. The ability of AMF to infect roots of L. chinensis, including colonization rate and infection intensity, and the effect of soil pH were measured. In total, 11 species from 4 different families were identified; 72.4% of species belonged to Glomus. One species, G. mossea, was found at all sites. High soil pH strongly decreased AMF species richness in natural saline-alkaline communities of L. chinensis, but did not affect spore density. Disturbance of soil through erosion may be an important factor influencing spore density in soil because AMF spores were seldom detected in bare soil where the surface had been significantly disturbed. Root colonization rate was positively correlated with infection intensity. The infection of L. chinensis roots was increased with increasing AMF species richness, depressed by increasing soil pH. Our research indicated that there was an abundance of AMF species in saline-alkaline grassland able to infect roots of L. chinensis, and suggested approaches for screening saline-alkaline tolerant AMF species with the potential to help restore the degraded grassland ecosystem on the Songnen Plain.