To study the effect of arbuscular mycorrhizal fungi (AMF) on the agronomic, physiological, and biochemical parameters of barley (Hordeum vulgare L.) grown on Cd contaminated soils of Iran, an experiment was carried out in Tehran, Iran for two seasons. The results showed that soil Cd caused a significant decrease in leaf area index (LAI), chlorophyll content, 1000 seed weight, and total dry mass per plant, whereas increased proline content, superoxide dismutase, and catalase enzyme activity were elevated by soil Cd. Mycorrhizal fungi significantly reduced the adverse effects of Cd and increased yield of barley. Decreased proline content, leaf antioxidant activity was also observed where mycorrhizal fungi were used. The use of mycorrhizal fungi had a positive mitigating effect on plant height, 1000 seed weight, chlorophyll contents, proline, LAI, root AMF colonization, foliar cadmium, catalase, peroxidase, and superoxide dismutase. Therefore, AMF have a potential to mitigate the effects of Cd pollution on soil. These results obtained formed a basis for future studies under open field condition before its application can be recommended to barley production under similar condition.