Abstarct: One of the most important factors of limiting crop yield in dry and semiarid regions is water shortage. Evaluation of yield in different stresses and using a variety of microorganisms in these regions, is one of the modern methods of sustainable agriculture for reducing damages caused by environmental stresses. Symbiotic of mycorrhizal fungi (AM) with roots of crops has shown positive effects in agricultural systems. In the present work, effects of two species of mycorrhizal fungi on water use efficiency of corn (Zea mays L.) baxsed on a randomized complete block design arranged as a split plot with three replications, at Research Station of Faculty of Agriculture, Ferdowsi University of Mashhad during the growing season of 20092010, were studied. Treatments were conducted with three mycorrhizal levels (control and two types of mycorrhizae (Glomus mosseae and Glomus intraradices)) and four irrigation levels (25%, 50%, 75% and 100% of the water requirement of irrigated corn). Grain yield, grain weight per ear, number of corn, biological yield, dry matter accumulation, leaf area index, plant height, canopy temperature, SPAD readings, relative water content, specific root length, root colonization percentage, and water use efficiency were determined. Results showed that all above mentioned traits were affected with both types of mycorrhizae, significantly (p”0.05) except number of corn which was not affected significantly (p•0.05). Type of mycorrhizae on root colonization percentage was not significant. The different irrigation levels had significant effect on all these traits (p”0.05). Generally, results showed that the use of mycorrhizae in low levels of irrigation can increase the absorption of water and nutrients by extending the root and increasing the absorbing surface. In this way, not only the plant resists against the water shortage more strongly, but also more dry matter will be produced for a specific value of water, which means the water use efficiency increases. Furthermore, the use of water and chemical inputs will be decreased.