Abstarct: the present study was conducted to investigate the effect of foliar application of nano iron oxide particles and biofertilizers on the quantitative and qualitative properties of of black cumin. a pot experiment with factorial arrangement in randomized complete block design with three replications as a pottery and a farm in the was carried out in 2017 growing season at the Faculty of Agriculture, University of Shahrood. The experiment consisted of three foliar application of nano iron oxide levels control, 1.5 and 3 g at 1 l water as the first factor and five level biofertilizers including Control, Glomus intraradices, Glomus mosseae, Azospirillum and Azotobacter solution as the second factor. The results of both pottery and field experiments resulted in an increase in the amount of photosynthetic pigments as a result of foliar application of nano iron oxide and inoculation with biofertilizers. Among the treatments studied, G. intraradices significantly increased grain yield and yield components significantly compared to control, and its role in increasing the amount of oil, essential oil, and thymokinone essential oil was very noticeable.The fungus increased the length and weight of roots and aerial parts of the plant, which in turn increased the absorption of nitrogen, phosphorus, potassium and iron in the roots, aerial parts and seeds. Inoculation with biofertilizers, especially G. intraradices, significantly reduced the activity of catalase, ascorbate peroxidase, and polyphenol oxidase enzymes. These enzymes were significantly increased by increasing the concentration of iron oxide nanoparticles, which appears to be due to the toxicity of excess iron in the plant. Also, considering the significant effect of foliar application of iron nanoxide in qualitative properties, it seems that the concentration of 1.5 grams per liter of iron nanoxide along with G. intraradices can improve the quantitative and qualitative characteristics of black cumin.