Ghrelin is a peptide hormone with orexigenic properties, primarily produced by the stomach. Different changes in fasting ghrelin levels have been reported following bariatric surgery. In this study, we investigate the hypothesis that because ghrelin is mainly produced by the fundus of the stomach, biliopancreatic diversion with sleeve gastrectomy with total resection of the gastric fundus and duodenal switch (BPD-DS) will cause substantial decrease in circulating ghrelin levels. Serum fasting ghrelin, leptin and adiponectin concentrations were measured by ELISA in 13 patients with morbid obesity who achieved weight loss by BPD-DS, before the operation and 18 months after. After BPD-DS, BMI decreased significantly, from 59.15±15.82 kg/m² to 32.91±6.46 kg/m² (P=0.001). Serum fasting ghrelin level decreased from 1.44±0.77 ng/ml to 0.99±0.35 ng/ml (P=0.019). Serum leptin level decreased from 1.81±0.38 ng/ml to 1.65±0.32 ng/ml, (P=0.196), and adiponectin level increased from 37.85±11.24 μg/ml to 39.84±16.27 μg/ml (P=0.422). BPD-DS is associated with markedly suppressed ghrelin levels, possibly contributing to the longlasting weight-reducing effect of the procedure. Leptin levels decreased and adiponectin increased, as expected, after weight loss. Sleeve gastrectomy with resection of the gastric fundus seems to be the main cause of the postoperative reduction in ghrelin levels.