The diversity of arbuscular mycorrhizal fungi (AMF) is of great interest because of their potential function in ecosystems. Tree peony is an important traditional ornamental and medicinal plant with economic significance. We examined the mycorrhizal status of the rhizosphere of 14 common cultivars of tree peony (Paeonia suffruticosa) in 3 different geographic locations in China. Root samples of all cultivars were colonized by AMF. The mean percentage of root length colonization, vesicles, and arbuscules were 39%, 3.6%, and 6.0%, respectively. AMF species richness varied from 5 to 11, and spore density ranged from 20 to 61 per 50 g of rhizospheric soil. The average AMF species diversity (Shannon-Wiener index) was 1.92, ranging from 1.64 to 2.18. A total of 31 AMF species belonging to 3 genera were identified in the rhizospheric soil. Glomus (21) was the dominant genus, followed by Acaulospora (7) and Scutellospora (3). G. aggregatum was the most commonly distributed species, with an occurrence frequency of 71.4 and a relative abundance of 13.6%. This study focused on the comparison of AM fungal diversity associated with tree peony in various original cultivar groups. This knowledge will help in selecting suitable AM inoculums for cultivation in the different original cultivar groups of tree peony. © Tübitak.