The effects of arbuscular mycorrhizal fungi on growth of ryegrass seedling were studied in cadmium contaminated soils by pot method.The results showed that：in severe pollution of Cd（Cd2+：180 mg/kg）condition，the infection rate of Glomus mosseae on ryegrass root was 30.23%，and it had good effect on the growth of ryegrass.The arbuscular mycorrhizal colonization alleviated the inhibition of cadmium pollution on ryegrass plant height，root length and biomass accumulation to a certain extent.Cadmium significantly reduced the chlorophyll content of ryegrass，the concentration of chlorophyll a was the lowest in severe Cd contamination treatment，and it decreased by 37.9% and 26.7% respectively in the treatment of not inoculated ryegrass and the treatment with the inoculation of ryegrass，compared with the control.Mycorrhizal inoculation significantly increased the chlorophyll content of ryegrass in both moderate and severe pollution of cadmium.Whether inoculation or not，the plant root activity were significantly decreased in severe cadmium contamination.but the vigor of plant root in inoculated plants decreased less than those of noninoculated plants.