BACKGROUND Laparoscopic sleeve gastrectomy (LSG) represents a relatively new restrictive operation for obesity. We report a prospective randomized study comparing two different techniques of performing this procedure. METHODS Between January and August 2006, 20 patients (group A) and 20 patients (group B) were prospectively and randomly submitted to LSG. The characteristics of the patients in the two groups were similar for age and sex. The median preoperative weight was of 120 kg (95-180) (A) and 133 kg (83-175) (B) (NS). The median preoperative BMI was of 42.5 kg/m2 (35-58) (A) and 47 kg/m2 (37-58) (B) (NS). The two techniques differ in that in A, stapling is performed after full devascularization and mobilization of the gastric curve, whereas in B stapling is performed as soon as the lesser sac is entered and the greater curve is devascularized after full completion of the sleeve. The staple-line is reinforced at the end of stapling in both techniques. RESULTS Median operative time was 34 min (12-54) (A) and 25 min (9-51) (B) (P = 0.06). Median peroperative bleeding was 5 mL (0-450) (A) and 5 mL (0-100) (B) (P = 0.37). Median number of staple cartridges used was 6 (5-7) (A) and 6 (4-7) (B) (P = 0.63). Peroperative complications were a small hiatal hernia requiring repair and a bleeding in two patients of A. Postoperative leak occurred in 1 patient of A, and minor early complications affected 2 patients of A and 1 patient of B. Peroperative and postoperative mortality was 0. Median hospital stay was 3 days (1-10) (A) and 3 days (2-7) (B) (P = 0.59). One stenosis as a late complication appeared in a patient of B. %EWL at 6 months and 1 year was respectively 43.4% (A), 42.2% (B) and 48.3% (A) 49.5% (B) (P = 0.82). CONCLUSIONS LSG can be performed by two different techniques. The technique B (section of the stomach followed by its mobilization) appears familiar to surgeons usually performing laparoscopic RYGBP. No observed differences are significant, but the technique B when looking at observed distributions, seems to be better than the technique A (mobilization of the stomach followed by its section) in terms of operative time, peroperative bleeding and hospital stay.