The effect of methanol eluates from Ginkgo biloba root on growth and development of arbuscular mycorrhizal fungi was studied under cultured in vitro. The study indicated that the methanol eluates from Ginkgo biloba root could significantly stimulate the spore germination and hyphal growth of arbuscular mycorrhizal fungi (Glomus mosseae, Gigaspora margarita), and the 80% methanol eluates had the most significant effect. There were rich flavonoids in the methanol eluates, and the highest flavonoids content was in the 80% methanol eluates. The mathematical analysis showed that there was a significantly positive correlation between the flavonoids content in the methanol eluates and the growth and development of arbuscular mycorrhizal fungi cultured in vitro.