Abstract: A pot experiment in a greenhouse was conducted to investigate the growth and nitrogen (N) uptake of Medicago sativa inoculated with different arbuscular mycorrhizal fungi [Glomus aggregatum (Ga), Glomus etunicatum (Ge), Glomus intraradices (Gi), Glomus tortuosum (Gt), Glomus versiforme (Gv)] or un-inoculated in soil without or with cadmium at two concentrations (6 and 12 mg Cd/kg). Mycorrhizal colonization of alfalfa inoculated with Ga, Gi, and Gt was 33.90%, 19.17%, and 31.95% lower, respectively, in 12 mg Cd/kg soil than in 0 mg Cd/kg soil. In soil without Cd, the biomass of the Gt-inoculated plants was 33.19%, 64.74%, 57.29%, and 34.91% higher than that in the Ga, Ge, Gi, and Gv treatments, respectively. In 12 mg Cd/kg soil, the biomass of the Gt-inoculated plants was 16.67%, 34.07%, 32.96%, and 52.76% lower than that of those inocluated with Ga, Ge, Gi, and Gv, respectively. Compared with uninoculated plants, those inoculated with Gv showed significantly increased shoot height, number of nodules, shoot biomass, total biomass, shoot N content, and total N content (by 65.41%, 95.24%, 61.87%, 50.30%, 5.83%, and 71.55%, respectively) in soil containing 12 mg Cd/kg. The N₄⁺-N and N₃^--N concentrations in soil significantly decreased with increasing Cd levels in the Gv-inoculation treatments. These results showed that Gv inoculation promoted the growth and N uptake of alfalfa in Cd-contaminated soils, whereas Gt inoculation could not benefit the growth of alfalfa grown in soils containing more than 6 mg Cd/kg.