Abstract: Arbuscular mycorrhizal (AM) fungi are important soil microorganisms in agroecosystems. Biodiversity among AM fungi in crop fields is influenced by many factors, including soil properties and plant species. In order to study AM fungal diversity in field soil of North China, we collected 127 soil samples from various crop fields from Shandong and Hebei provinces. Culture and purification of the mycorrhizal fungi led to the isolation of 22 species in five genera. Among these, 20 species were identified, including a new record for China, Glomus spurcum Pfeiffer, Walker & Bloss. The frequency of occurrence of the genus Glomus was the highest and Acaulospora was the second most common genus, while Glomus etunicatum and G. mosseae were dominant species. Spore density was affected by soil Olsen-P content and pH, while species diversity was little affected. Moreover, AM fungi species colonization and diversity was greatly affected by host plants. Although AM fungi hosted by maize and sweet potato had similar dominant species, there were differences in species composition.