The cause of all small bowel obstruction in 60–75% of cases is adhesive development. The first and main method for adhesion prevention is undoubtedly the surgical technique, but the prevention of adhesive development is still actual. We aimed to study macroscopic and microscopic peculiarities of the intestine, peritoneum, and scars of the anterolateral abdominal wall. Also, immunological blood changes were observed in rats with the experimental created adhesive disease on the background of azathioprine introduction. The experiment was conducted on 40 rats divided into 2 subgroups: 20 animals as an experimental group (EG1) and 20 as a control group (CG1). Animals from EG received azathioprine (Moshimerampreparaty named by N.A. Semashko, Russia) in a dosage of 1 mg/100g of weight once a day for the first 3 days (starting from the day of surgery). The control group did not receive any drugs. All 40 rats survived the postoperative period. Rats were removed from the experiment on the 7^th day after the operation. There were significant statistical differences in most indicators between the experimental and control groups. Phagocytic index (PI) was reduced by 4.55 due to the natural reaction of the rat organism to the surgery. Indicators of EG were a slight decrease in leukocytes and lymphocytes by 0.3 and 0.9, respectively, a moderate decrease in T-lymphocytes by no more than 2.0, and a decrease in phagocytic activity by 5.8. Immunosuppression with azathioprine significantly reduced the frequency and severity of the adhesive process of the abdominal cavity. Used in the recommended dose does not significantly inhibit important indicators of immunity and does not affect wound healing processes.