The parameters systems of immunity was analyzed in 56 patients with duodenal ulcer (DU) and 36 healthy persons. The suppression of T-system and its subsets, a tension of humoral link of immunity was observed in patient. The use traditional method of treatmend was not made a result to disorder of second immunodificiency in patients with DU (group 1). The usage of immunomoduline, the dose of which was 1.0-1.2 mg (in one course) at second group patients (n=24) with DU cured immune disorder, increased cell immunity, and had immunocorrection and eradication features.