Abstract: Effect of arbuscular mycorrhizal(AM)fungi Glomus versiforme Berch and mixed inoculaGlomus mosseae Nicolson and Gedermann+Sclerocystis sinuosa(Gerd．Bakshi)Almeida and Schenckon growth and yield of peanut and sweet potato were investigated under field conditions．Results show that AM fungi can improve health status of pea nut seedlings and the number of fruits per plant．increase 21．3％ of yield per hectare compared to the contro1．However the growth and yield of sweet potato are not increased，and its plant length and weight of stem with leaves are reduced by the inoculation with Glomus versiforme，while the vegetation growth and the numbers of fruits per plant are significantly enhanced by inoculation with the mixed inocula of AM fungi，and the yields per plant and per hectare are 1．6 and 1．4 times respectively greater than those of the contro1． It is suggested that the different species of AM fungi should be used for various crops when applied in field．