Objective <p>Anastomotic stricture (AS) is a common complication following low-level anastomosis of the colon and rectum in rectal cancer (RC) surgery. The aim of this study is to evaluate whether intraoperative stay sutures combined with postoperative anal dilatation reduce the incidence of AS after low anterior resection with defunctioning stoma.</p> Methods <p>A total of 240 patients with low RC who underwent treatment at the Ninth Medical Center of the PLA General Hospital between February 2019 and May 2024 were randomly assigned to four groups (<i>n</i> = 60 each): one experimental group and three control groups (A, B, and C). The experimental group underwent intraoperative placement of stay sutures at the anastomotic site under anoscopic guidance during low anterior resection with defunctioning stoma, with 3 to 4 radial transanastomotic sutures placed across the anastomotic line. Postoperative anal dilatation was initiated two weeks after surgery. Control group A received only intraoperative stay sutures; control group B received only postoperative anal dilatation; control group C received neither intervention. The incidence of AS was evaluated 1 to 2 months postoperatively, with follow-up continuing from 2 months to 1 year.</p> Results <p>The incidence of AS was 0% in the experimental group, 2% in control group A, 7% in control group B, and 48% in control group C.</p> Conclusion <p>The combined use of intraoperative stay suture placement and postoperative anal dilatation was effective in preventing AS following low anterior resection with defunctioning stoma in patients with RC. Intraoperative stay sutures also provided additional benefits in reinforcing anastomosis and achieving hemostasis. Owing to its simplicity, safety and clinical utility, this strategy may be considered for broader application in surgical practice.</p>