In experiment on 50 white mongrel male rats there were investigated postoperative morphological changes in the area of a potential formation of colorectal anastomosis, occurring after total rectal mobilization performance. There was established, that rectal mobilization, even while securing a blood flow along the main vessels, causes nonreversible ischemic disorders in its wall. The investigation results witness the enhanced risk of the sutures insufficiency occurrence in low colorectal anastomoses and substantiate the expediency of application of prophylactic methods for this complication in a clinical practice.