Objective To analyze the effect of preserving the left colon artery in minimally invasive surgery for rectal cancer. Methods From January 2018 to December 2019, 60 patients with rectal cancer undergoing minimally invasive surgery were selected and grouped according to whether they had retained the left colon artery. Thirty patients in the test group retained the left colon artery and thirty patients in the control group did not retain the left colon artery. The perioperative indicators, surgical outcome, postoperative recovery and follow-up were compared between the two groups. Results There were no significant differences in intraoperative blood loss, distance between anastomotic site and dentate line, tumor diameter, number of lymph node dissection and operation time between the two groups (P>0.05). The incidence of free splenic flexure, ischemic change of residual ends and anastomotic fistula was found to be lower in the experimental group than that in the control group (P<0.05). However, there was no significant difference in the incidence of abdominal infection, intestinal obstruction, incision infection (P>0.05). There was no significant difference in postoperative time of getting out of bed, exhaust and hospitalization between the two groups (P>0.05). Comparison of metastasis rate and recurrence rate after postoperative follow-up between the two groups showed no significant difference (P>0.05). Conclusion The preservation of the left colon artery in minimally invasive surgery for rectal cancer has a good effect, which is equivalent to the preservation of the left colon artery. It can significantly reduce the incidence of free splenic flexure, ischemic changes of the stump, anastomotic fistula, and does not increase the long-term metastasis rate and recurrence rate, which can promote postoperative rehabilitation of patients, and is worthy of popularization and research.