Background: The best treatment options for walled-off pancreatic necrosis (WOPN) are not well defined. A retrospective study of patients treated for WOPN with transgastric debridement and internal drainage was undertaken. Methods: Patients with symptomatic non-infected WOPN treated with open transgastric debridement and internal drainage were evaluated. Results: In all, 51 patients underwent surgical management of necrotizing pancreatitis during the study period. Ten patients (19%) were treated with open transgastric debridement and internal drainage for symptomatic non-infected WOPN. The median patient age was 40 years, the most common aetiology for pancreatitis was biliary, the mean American Society of Anesthesiologists (ASA) score was 2 and the delay to surgery was 100 days. The operating time was 118 min, with a blood loss of 50cc. One patient required reoperation, three patients had morbidity and there were no mortalities. The only factor associated with post-operative morbidity was the presence of positive cultures (P < 0.05). The length of stay (LOS) after surgery was 8 days, at a median follow-up of 18 months, one patient had late complications related to the surgery and the procedure was successful in 90% of the patients. Discussion: Open transgastric debridement with internal drainage of WOPN is safe and efficacious. Patients were clinically stable (no organ failure) and had a long delay in surgical intervention (100 days). In this select group of patients, the success, morbidity and mortality is similar to all reported minimally invasive techniques.