The purpose of the work was to evaluate the effectiveness of the elimination diet in infants with gastrointestinal manifestations of food allergy.Patients and methods. 84 children aged 2 months to 1 year were examined with gastrointestinal food allergy to cow's milk proteins. All children were prescribed an elimination diet with the exclusion of cow's milk proteins. An assessment was made of the regression of gastrointestinal symptoms on day 3, 7 and 14 of diet therapy and the determination of the concentration of eosinophilic cationic protein in serum. The general-clinical, immunological, allergological and statistical methods of research were used.Results. The purpose of the elimination diet with the exclusion of cow's milk proteins for nursing mothers and the use of mixtures with extensive hydrolysis of protein in the case of artificial feeding leads to a complete regression of gastrointestinal and skin symptoms in all examined children on the 14th day of diet therapy, which is further confirmed by the normalization of the concentration of eosinophilic cationic serum protein in diet therapy. Conclusions. Elimination of cow's milk proteins in infants with gastrointestinal food allergy results in complete regression of gastrointestinal and skin symptoms on day 14 of diet therapy, and determination of the concentration of eosinophilic cationic protein in serum can be used as an additional criterion for the effectiveness of diet therapy.