Obesity can lead to serious complications, and bariatric surgery, such as Single Anastomosis Sleeve Ileal (SASI) bypass, becomes a valuable option when conventional treatments fail. This innovative technique combines a sleeve gastrectomy with a single anastomosis intestinal bypass, reducing operative risk and time. We present the case of a 27-year-old woman with morbid obesity and metabolic syndrome who underwent a SASI procedure. The operation and postoperative course were uneventful, and the patient achieved a 30 kg weight loss at 7 months, stabilizing at 80 kg. This case illustrates the potential of SASI as a promising alternative in bariatric surgery. However, long-term studies are needed to evaluate its durability and nutritional safety.