The percent of N and C composition in spores or sporocarps of different species of two genera of VA mycorrhizal fungi—Gloraus and Sclerocystis were analysed. It was found that culture period effects the percent of N,C and their ratio, although the influences of host and origin of strain of fungi on those appeared to be low. N,C percentage and their ratio in spores or sporocarps were variable among fungal species of a same genus, but difference between two genera was significantly. This technology may serve as a supplementary indicator for classification and identification of VA mycorrhizal fungi.