Regression of Barrett's esophagus may occur after effective anti-reflux surgery. Roux-en-Y gastric bypass (RYGBP) is an effective operation to treat morbid obesity. In addition, it provides complete relief of gastroesophageal reflux disease (GERD). Regression of Barrett's has not been reported after RYGBP. We performed a laparoscopic Roux-en-Y gastric bypass on a patient with GERD and Barrett's esophagus. At 1 year after the RYGBP, an upper endoscopy was performed as routine surveillance for the patient's Barrett's esophagus; endoscopic and histologic evaluation demonstrated complete regression of the Barrett's esophagus. The patient lost one-third of her preoperative weight and had resolution of her reflux symptoms. RYGBP limits the amount of acid reflux and completely diverts bile away from the esophagus. This may lead to the regression of Barrett's esophagus.