Water stress is one of the most important factors affecting plant performance. Considering the potential effect of mycorrhizal fungi on modulating the effect of water stress on the performance of Borage , an experiment was conducted as split-plot in randomized complete block design. Water stress as the main factor in irrigation levels after 30, 60, 90, 120 and 150 mm water evaporation from evaporation pan class A and mycorrhiza fungi as sub-agent in levels of non-application, application of Glomus mosseae and G. intraradices species were considered. For flower mucilage, the interaction of irrigation and mycorrhizal fungus was significant, and at the irrigation level of 120 and 150 mm, water evaporation increased the water stress and caused a decrease in flower mucilage. At the irrigation levels after 90, 120 and 150 mm of water evaporation, , the reduction of proline and soluble sugar of borage was observed after 60, 90, 120 and 150 mm of water evaporation in the presence of mycorrhizal fungus compared to the absence of fungus application. Based on the results, irrigation treatment is recommended after 90 mm of water evaporation and the application of mycorrhizal fungus G. mosseae.