We aimed at comparing our long-term results after biliopancreatic diversion (BPD) with or without gastric preservation for morbid obesity. Between 1999 and 2009, we performed 540 BPD: 287 patients (group A) underwent BPD with distal gastric resection (BPD-AHS) and 253 (group B) underwent BPD associated with transitory vertical gastroplasty (TGR) with duodenal switch (DS). The results have been analyzed in terms of weight loss, improvement of comorbidities, and quality of life (Bariatric Analysis and Reporting Outcome System). The mean follow-up was 7.4 ± 2.9 years. One year after surgery, mean initial excess weight loss percentage was 69% for patients in group A (n = 287) and 65% for group B (n = 253); after 2-5 years, it was 74% for patients who underwent BPD-AHS (n = 130) and 75% for patients who underwent BPD-TGR-DS (n = 116); it was 71% and 74% for patients in group A (n = 157) and B (n = 137), respectively, followed up for >5 years (P = 0.27). Among the diabetic patients in both groups (191 patients), 64% discontinued the medication with insulin (P = 0.25), and 98% had stopped oral drugs within 1 year from surgery (P = 0.29). We did not observe deficiencies of vitamins and proteins. The overall incidence of incisional hernias was 38% (P = 0.35). We recorded 13 anastomotic ulcers (2.4%; P = 0.28). BPD represents, in spite of the side effects, an effective technique for treatment of morbid obesity and its associated diseases. Moreover, our results showed that patients who underwent BPD-TGR-DS had slightly better results in terms of postoperative metabolic complications and improvement in quality of life.