Gastroesophageal reflux disease (GERD) is a widespread health issue, often managed surgically by fundoplication in nonobese patients unresponsive to medical treatment. With obesity rates rising globally—closely associated with increased GERD—morbidly obese patients with prior fundoplication have become more prevalent. While Roux-en-Y gastric bypass (RYGB) addresses both obesity and GERD, its main drawback is the exclusion of the stomach and duodenum from future endoscopic access, posing risks in patients predisposed to gastric cancer. This case series evaluates a novel surgical approach— Functional Roux-en-Y Gastric Bypass with Diverted Sleeve Gastrectomy (FRYGB-DSG) which anatomically mimics transit bipartition and functionally resembles RYGB, while maintaining access to the entire gastrointestinal tract. Three patients with prior Nissen fundoplication developed morbid obesity: one had GERD relapse and hiatal hernia, the others were asymptomatic (one with a small hiatal hernia). All had strong family histories of gastrointestinal cancer and declined procedures that would exclude GI segments. GERD was assessed through validated questionnaires and endoscopy. The FRYGB-DSG technique involved dismantling the fundoplication, repairing hiatal hernia (if present), crura adjustment and performing a sleeve gastrectomy, initiated 3 cm from the pylorus, followed by a wide antral wedge resection and a Rouxen-Y gastroileostomy, favoring alimentary flow via the anastomosis. The biliopancreatic limb was 40% of total intestinal length and the alimentary limb was 80 cm long. All surgeries were performed by a single surgeon, with 12 months of follow-up. Postoperatively, all patients achieved complete GERD symptom resolution, no endoscopic signs of esophagitis, with comparable weight loss to standard RYGB. FRYGB-DSG may thus provide an effective alternative for morbidly obese patients with prior fundoplication, without gastrointestinal exclusions. Further studies are necessary to validate these findings.