There were examined 35 patients after performance of operations for complicated ulcer disease. To the first group were incorporated 9 (25.7%) patients, in whom palliative operations were done, to the second group--9 (25.7%) patients, to whom vagotomy with gastric drainage operation was performed, and to the third group--17 (48.6%) patients, in whom gastric resections were applied. After palliative operations patholologic mucosal changes were localized predominantly in gastric antrum and duodenal ampulla. In 89% of observations mucosal pathology was associated with H. pylori. In 77.8% of the examined patients of second group the mucosal contamination by H. pylori was revealed. The relation was determined between gastric antrum mucosal inflammation and H. pylori infectioning. After gastric resection more significant signs of mucosal inflammation were observed in gastric stump and anastomotic region in comparison with such in efferent intestinal loop. Studying of gastroduodenal mucosa, using histological investigations after surgical treatment of complicated ulcer disease permits to reveal the character of mucosal pathological changes after performance of various operations and, taking it to account, to elaborate the individualized program of the patients rehabilitation.