Abstract: The disease resistance of maize toward sheath bligh tinduced by arbuscular mycorrhizal fungi was studied. The results show that the disease incidence and disease index of mycorrhizal maize plants are decreased significantly. The growth of maize plants is promoted as well when they are inoculated with Glomus mosseae. The mycorrhizal infection rate of maize plants is decreased when they are attacked by pathogen. It is proved that there are interactions between G. mosseae and R. olani.