Abstract: Objective:To analyze and compare the effect of low ligation and high ligation of inferior mesenteric artery（IMA）and root lymph node dissection in laparoscopic radical resection of low rectal cancer.Methods:The clinical data of 92 patients with low rectal cancer who underwent laparoscopic radical resection from April 2015 to March 2018 were analyzed retrospectively.According to the mode of intraoperative IMA ligation，the patients were divided into high group（n=52）and low group（n=40）.The operation time，blood loss，number of IMA root lymph node dissection，hospitalization time ，postoperative complication rate and defecation function were compared between the two groups.Results:There was no significant difference in operation time [（142.24±20.25）min VS（146.24±22.64）min]，blood loss [（40.36±6.18）ml VS（44.66±7.22）ml]，lymph node dissection number [（14.24±2.18）VS（13.94±2.07）]，hospitalization time [（11.49±3.14）d VS（12.48±3.85）d] between the two groups（P>0.05）.The first exhaust time of the low group was lower than that of the high group [（36.63±2.78）h VS（44.48±4.21）h].The defecation function score of the two groups at 3 months and 6 months after operation was better than that of the high group，and the difference was statistically significant（P<0.05）.The incidence of anastomotic leakage in the low group was 2.5%（1/40），lower than that in the high group [5.78%（3/52）].The difference was statistically significant（P<0.05）.The incidence of urinary incontinence or sexual dysfunction in low group was 17.5%（7/40），higher than that in high group[7.69%（4/52）]，the difference was statistically significant（P<0.05）.There was no significant difference in the incidence of other complications（P＞0.05）.onclusion:The two kinds of ligation have similar curative effect in laparoscopic radical resection of rectal cancer，but low ligation has less influence on defecation function，lower incidence of anastomotic leakage and better shortterm curative effect.

Key words: inferior mesenteric artery, laparoscopy, rectal cancer