Background: Often detected incidentally, retrorectal tumors frequently require resection secondary to possibility of malignancy, development of infection, and localized growth with compression. The surgical approach is summarized to abdominal, posterior or a combination, depending on the location of the retrorectal mass and its relationship to the pelvic sidewall. Laparoscopic transabdominal resection of retrorectal tumors has shown safety and efficacy. Robot technology offers a stable platform with superb optics, and endo-wristed instruments that can facilitate dissection in the narrow pelvis. We present the emerging new technique of robot-assisted minimally invasive approach to a retrorectal mass in an obese female.Methods: An obese 35-year-old female, body mass index (BMI) 41 kg/m 2 , with an incidental 2 cm cystic retrorectal lesion involving the pelvic sidewall was taken to the operating room for a robot-assisted minimally invasive resection of the mass.Results: Total operative time was 2 hours and 30 minutes, and total robotic dissection at 70 minutes. The patient was discharged on postoperative day 2. Final pathology revealed a benign Mullerian type cyst, 2.2 cm in greatest dimension.Conclusions: Robot-assisted minimally invasive resection of a retrorectal mass is safe and feasible. This method can be particularly useful in the narrow pelvis and with obese patients.