BACKGROUND Along with the development of technology, robotic approach is being performed for laparoscopic Roux-en-Y gastric bypass (LRYGB). Some literatures reported same or better peri-operative outcomes with the robotic procedure. The aim of this study is to compare our experience in robot-assisted LRYGB (RA-LRYGB) with LRYGB in terms of peri-operative outcomes. METHODS From January 1, 2012 to April 30, 2014, a total of 270 patients underwent LRYGB by one surgeon at a single institution. Of these, 64 cases were done robotically. A retrospective review was performed for these patients, noting the outcomes and complications of the procedure. RESULTS The 64 RA-LRYGB patients had a mean age of 45.9 ± 10.0 years (range, 23-67) and a mean preoperative body mass index (BMI) of 48.4 ± 7.9 kg/m(2) (range, 33.8-76.4). The 207 LRYGB patients had a mean age of 45.0 ± 10.7 years (range, 21-67) and a mean preoperative BMI of 48.4 ± 8.1 kg/m(2) (range, 34.0-80.4). These two groups were clinically comparable. Mean length of hospital stay was 3.0 ± 4.1 days (range, 1-19) in RA-LRYGB patients, significantly longer than 1.6 ± 1.7 days (range, 1-17) in LRYGB patients (p < 0.01). Thirty-day readmission rate was 9.3% (n = 6) in the RA-LRYGB group and 6.8% (n = 14) in the LRYGB group. Higher leak rate was noticed in RA-LRYGB patients at 7.8% (n = 5), compared to 0.5% (n = 1) in LRYGB patients (p < 0.01). All the leaks occurred at the pouch level in the RA-LRYGB group, while one leak from the LRYGB group occurred at the gastrojejunal anastomosis site. CONCLUSIONS Robot-assisted Roux-en-Y gastric bypass may result in higher leak rate at the pouch level, when compared to that of laparoscopic procedures.