Laparoscopic pyeloplasty (LP) for the repair of ureteropelvic junction (UPJ) obstruction provides results similar to those of open pyeloplasty with less morbidity, but its use has been limited, as it requires advanced laparoscopic skills. Robotic computer-assisted pyeloplasty (RAP) has the potential to reduce the technical challenges of the reconstructive portion of the operation. We compare our RAP experience with our recent LP cases.Fourteen patients underwent LP, and 31 underwent RAP. The demographics of the two groups were similar. Three patients in the RAP group had been treated previously for UPJ obstruction. All procedures were performed transperitoneally. For RAP, conventional laparoscopic dissection and exposure preceded robot-assisted reconstruction. A Double-J stent was placed cystoscopically in all patients. Patient demographics and operative, postoperative, and follow-up data were compared. Success was defined strictly as the unequivocal absence of both obstruction and postoperative pain. Also technical success was defined as no evidence of persistent high-grade obstruction, no loss of function, no symptomatic obstruction, and no necessity for further treatment.The diagnosis of UPJ obstruction was confirmed intraoperatively in all cases. No difference was found in operative and postoperative outcomes of the two procedures. Operative time, including cystoscopy, was 299 minutes in the LP group and 271 minutes in the RAP group. The median estimated blood loss was <100 mL in both groups. The median console time for RAP was 76 minutes (range 54-124 minutes) and consisted of preparation and completion of the anastomosis. The median robotic docking and undocking time was 16 minutes (range 5-30 minutes). The anastomotic times for LP were not recorded. There were no conversions to open surgery and no intraoperative complications. The mean length of stay (LOS) was 2 days in both groups. There were two postoperative complications in each group: In the LP group, one large retroperitoneal hematoma and one umbilical hernia; in the RAP group, one nonfebrile urinary-tract infection and one urine leak. The mean follow-up was 10 months (range 1-31 months) for LP and 6 months (range 1-21 months) for RAP. Strict success was seen in 64% of the LP patients and 66% of the RAP patients. There was one technical failure in the RAP group, resulting in a technical success rate of 100% for LP and 97% for RAP. Technical success was seen in two LP patients and five RAP patients with partial obstruction on early postoperative renography and three LP patients and four RAP patients with occasional postoperative pain.Robotic computer-assisted pyeloplasty provides short-term results similar to those of conventional laparoscopic pyeloplasty at our institution.