PURPOSE: The aim of this study was to determine the advantages of adequate PTGBD in patients with acute complicated cholecystitis. METHODS: We performed a retrospective review of a database that was collected from September 2001 to July 2008. Acute cholecystitis with gangrene or perforation was defined as acute complicated cholecystitis. A PTGBD was performed for the patients immediately after the diagnosis using US or CT and then a tubogram was performed after 5~7 days. After evaluating the gallbladder (GB) and common bile duct (CBD) with a tubogram, we removed the drainage and the patients underwent a LC after readmission. RESULTS: Three hundred seventy four of the 893 patients who were diagnosed with acute cholecystitis underwent PTGBD. While 19 (3.2%) of the total acute cholecystitis patients were converted to open cholecystectomy due to severe inflammation, 14 (3.7%) acute complicated patients were converted to open cholecystectomy. In 79 patients, the pre-operative tubogram showed the presence of CBD stone and so ERCP was performed. There was no post-operative death. CONCLUSION: Performing PTBGD in patients with acute complicated cholecystitis allows the early relief of the symptoms of acute cholecystitis. This allows for sufficient evaluation and treatment for CBD during the PTGBD state. Further, PTBGD decreases the mortality and morbidity in the high-risk patients due to sufficient evaluation and management of the underlying critical disease. PTBGD allows for performing elective cholecystectomy when the patient is in a better condition for surgery. Therefore, PTGBD can be useful for treating acute complicated cholecystitis.