Abstract: This paper summarizes the role of ectomycorrhizal fungi in plant C and N metabolisms,inorganic nutri-tion of P and K,and characteristics of hormone and resistant substances produced by mycorrhizal fungi.It concludes that the principal role of mycorrhiza is the absorption,transformation and storage of nutri-ents for plants. Certain mechanisms of the symbiotic nutrition between mycorrhizal fungi and plants are investigated.