This study investigates the effectiveness of preoperative very low-calorie diet (VLCD) in laparoscopic cholecystectomy. A prospective observational study of consecutive patients undergoing laparoscopic cholecystectomy was undertaken. At the preoperative visit, all patients were advised to adhere to VLCD for 2 weeks before surgery (<800 kcal/d). Patients were judged to have complied with the VLCD if weight loss >2 kg. Technical difficulty was assessed using questionnaires. A total of 38 patients met the inclusion criteria. Difficulty of visualization and dissection of Calot’s triangle in obese patients was twice that of nonobese patients (P=0.01). In 62% of procedures involving obese VLCD noncompliant patients, the surgeon experienced ≥1 area of technical difficulty, compared with 0% of procedures on obese, compliant patients (P=0.018). Difficulty of dissection of the gallbladder bed was 3 times higher in obese, noncompliant patients, compared with obese, compliant patients (P=0.07). Adherence to a 2-week preoperative VLCD may reduce technical difficulty of laparoscopic cholecystectomy in obese patients.