Objective. The objective is to analyze molecular and genetic mechanisms of endothelial dysfunction development in children with allergic enteropathy.Methods: We have studied the polymorphisms of endothelial nitric oxide synthase gene and the level of nitric oxide metabolites in coprofiltrates in 43 children aged from 6 months to 3 years with allergic enteropathy.Results: The endothelial dysfunction in allergic enteropathy is associated with nitric oxide molecule. Carriage of the homozygous allele СС Т786С of the endothelial nitric oxide synthase gene raises the risk of IgE-independent food allergy development by 8.8 times.Conclusions: The conducted study evidences the active participation of nitric-oxidergic mechanism in allergic inflammation development.