PURPOSE: Although some limitations of conventional laparoscopy have been overcome by the enhanced dexterity of a robotic system, few studies have reported the use of robotic surgery for rectal cancer. This study analyzed prospectively the safety, morbidity, mortality and operation time of a robotic rectal resection for rectal cancer. METHODS: The data of 185 consecutive patients, who had undergone robotic rectal resection for rectal cancer at Korea University Aanam Hospital from July 2007 to April 2011, was analyzed prospectively. The postoperative outcomes and operative times were evaluated. RESULTS: Robotic rectal resection using a da Vinci surgical system was performed on 185 patients. There were 115 low anterior resections, 5 anterior resections, 1 Hartmann's operation, 10 ultra-low anterior resections, 43 intersphincteric resections and 11 abdominoperineal resections. The median hospital stay was 9 days. The overall morbidity rate was 33.4%. There was one conversion to open surgery. The mean passage of flatus was noted on postoperative day 2.0, diet was started on postoperative day 2.3 and the mean postoperative hospital stay was 13.7 days. The mean number of retrieved lymph nodes was 16. The total operation time decreased with increasing operator experience (306 min vs 285 min vs 268 min, p=0.009). CONCLUSION: A robotic rectal resection is feasible and safe for rectal cancer patients. The data showed an acceptable morbidity and mortality rate compared to the short term results of conventional laparoscopic and open surgery reported previously. Nevertheless, the oncologic and functional benefits of robotic colorectal surgery should be evaluated through a large scale study.