155 patients with cancer of proximal rectum and sigmoid colon complicated by acute ileus were included and divided into 2 groups. Postoperative complications have arisen in 5 (5.3%) patients of group I and in 11 (18.4%) patients of group II. Anastomotic leakage has arisen only in 1 patient in the basic group (1.1%) and in 7 (11.7%) patients of the compared group on the 5th-12th day after operation. We have worked out the rate score of risk factors of anastomotic leakage. А score was given for each AL factor which we had selected for elaboration of this scale. The lowest point which we received during this analysis was 7 and the highest was 32. For better analysis of the proposed scale, we have constructed comparing ROC curve between sensitivity and specificity of AL risk index. The area under this curve is 81.8%, which is a good index and it indicates that the proposed risk scale is a good method to identify patients who are at high risk of AL development (95% confidence interval of this area ranges from 73.1% to 90.5%).