Objective To compare the effects of double stapling technique （DST） and single stapling technique （SST） in the low or ultralow anterior rectal resection and colon-anal canal anastomosis for patients with rectal cancer. Methods The clinical data of 351 patients with rectal caner， who were treated with low or ultralow anterior resection and colon-anal canal anastomosis in West China Hospital from Jan. 2009 to Dec. 2010， were collected and analyzed retrospectively. Operative and postoperative indexes of patients treated with DST （n=302） and SST （n=49） were compared. Results Compared with DST group， the distance from the dentate line to the edge of tumor， the length of the distal surgical margin 〔（1.83±0.59） cm vs. （2.07±0.56） cm〕， and hospitalization cost 〔（24 350.48±7 812.73） yuan vs.（29 455.32±7 869.33） yuan〕 of SST group were shorter or lower （P＜0.05）， but operative time was longer 〔（112.86±39.29） min vs. （100.10±36.75） min， P＜0.05〕. There were no significant differences on blood loss， duration of firstambulation， duration of first passing flatus， duration of first bowel movement， duration of pulling out nasogastric tube， duration of pulling out urinary catheter， duration of pulling out drain， postoperative hospital stay， total length of hospital stay， and the incidence of complication between the 2 groups （P＞0.05）. All patients were in functional recovery of anal control after operation. All patients were followed-up for 6-24 months （average 16 months）. During the followed-up， only 1 case suffered local tumor recurrence （SST group）， 3 cases suffered distant metastases （all in DST group）， and 15 cases （4.27％） died， of which 13 cases （4.30％） in DST group and 2 cases （4.08％） in SST group. Conclusions As in the low or ultralow anterior rectal resection and colon-anal canal anastomosis for patients with rectal cancer， SST results in shorter distal surgical margin than DST， so SST is suitable for the patients with shorter distance from the dentate line to the edge of tumor. What’s more， it saves the hospitalization cost effectively.