Abstract: Objective:To investigate the safety and feasibility of laparoscopic surgery with reduced orifice in the treatment of sigmoid colon and upper rectal cancer.Methods:90 patients with sigmoid colon or upper rectal cancer were recruitedfrom January 2018 to may 2019.The patients were randomly assigned to the conventional laparoscopic surgery group and the reduced orifice laparoscopic surgery group，with 45 cases in each group.The preoperative general conditions，intraoperative bloodloss，operation time，exhaust time，outofbed activitytime，hospitalizationtime，hospitalizationexpenses，bowel resection length，incidence of complications，number of resected lymph node and postoperative pain score were compared.Results:The total incision length and postoperative pain score of the two groups were（6.9±0.7）cm and（1.9±0.8），respectively，which were lower than those of the convention laparoscopic surgery group（9.3±0.7）cm and（2.3±0.6），the difference was statistically significant（P<0.05）.There was no significant difference in operation time，intraoperative bloodloss，bowel resection length，exhaust time，outofbed activitytime，hospitalizationtime，hospitalizationexpenses，number of resected lymph node，incidence of postoperative complications，recurrence rate，distant metastasis rateand Diseasefree survivalbetween the two groups（P>0.05）.Conclusion:It is safe and feasible to treat sigmoid colon and upper rectal cancer by laparoscopy surgery with reduced orifice.

Key words: reduced incision, 〓sigmoid colon cancer, 〓upper rectal cancer, 〓effectiveness