Introduction. Type 1 diabetes mellitus (DM-1) and its complications pose a serious medical and social problem. Erosive changes in the gastric mucosa are among the most common lesions of the digestive system in diabetes mellitus, and can lead to life-threatening gastrointestinal bleeding and early disability of patients.Aim. Substantiation of the effectiveness of rebamipid course treatment based on an assessment of the functional state and antioxidant activity of the supraepithelial gastric mucosa in chronic erosive gastritis in patients with DM-1.Materials and methods. A comprehensive examination of 12 DM-1 patients with erosive gastritis and 11 healthy individuals was carried out, including FGDS with biopsy of the antrum mucosa and stomach body, exclusion of Helicobacter pylori infection, determination of the biochemical composition of structural glycoproteins of mucus and the concentration of degraded glycoproteins, evaluation of the antiradical activity of the supraepithelial mucous layer of the stomach.Results and discussion. In chronic erosive gastritis in patients with DM-1, a significant predominance of degraded monosaccharides in the supraepithelial mucous layer of the stomach was revealed (6 times higher than in healthy individuals), a decrease in the concentration of polymerized glycoproteins in gastric mucus (21% vs. 80%) and a significant increase in the antiradical activity of mucus. Course  treatment of chronic erosive gastritis in patients with type 1 diabetes with rebamipid at a dose      of 100 mg 3 times a day for 3 weeks contributes to the normalization of the indicators of glycoproteins of native mucus, antiradical activity of the mucosa and complete epithelization of the erosions of the antrum of the stomach.Conclusions. The use of rebamipid in the treatment of chronic erosive gastritis in patients with type 1 diabetes contributes to reducing the degradation of polymerized glycoproteins of native mucus, normalizing the antiradical activity of the mucosa and complete epithelization of erosions of the antrum of the stomach.