Objective To explore the application of left colon artery and retention of anal canal in rectal cancer anterior resection .Methods 134 patients with rectal resection were divided into two groups by random number table.The observation group (n=67) received anterior resection of the left colonic artery and retained anorectal anterior resection.The control group(n=67) received subconjunctival artery root ligation ,non -retained anorectal anterior resection of rectal cancer .The number of lymph node dissection and the incidence of postoperative anastomotic leakage were compared between the two groups .The rate of reoperation was compared between the two groups .Results The number of lymph node dissection in the observation group and control group was (4.2 ±1.3),(4.4 ±1.2),the difference was not statistically significant (P=0.450).The incidence rate of anastomotic leakage was 2.99％ in the observation group,which was 11.94％in the control group,the difference was statistically significant (χ2 =3.890,P=0.049).Conclusion In the case of no difference in preoperative and postoperative perioperative management ,the left colonic artery and the anal canal were retained in the rectal cancer without affecting the lymph node dissection in No.253 group,but it could provide sufficient blood for the anastomosis ,to reduce the risk factor of the occurrence of anastomotic leakage .