Cholethoraxis a bilious pleural effusion caused by abnormal communication of the biliary system with the thoracic cavity. It can be a rare complication of percutaneous transhepatic gallbladder drainage (PTGBD). We present the case of 88-year-old man who was diagnosed as cholethorax with cutaneous fistula mimicking parapneumonic effusion following PTGBD. A 88-year-old man admitted acute cholecystitis with large gallstone two months ago. He underwent PTGBD and was discharged 3 weeks later. One month after discharge, the patient returned complaining fever, cough and dyspnea. Chest radiograph revealed a large amount of right pleural effusion. A percutaneous pleural drainage tube was inserted and approximately 700 ml of yellow-ish, turbid fluid was drained initially. Biochemical studies of this fluid revealed: pH 7.5, RBC 4320/mm3, WBC 5280/mm3 (neutrophil 86%), lactic dehydrogenase 124 mg/dL, protein 2.6 g/dL, glucose 123 mg/dL. A parapneumonic effusion was sus-pected, but abdominal CT showed pleurobiliary fistula. Additional laboratory studies of pleural fluid revealed total bilirubin 1.52 mg/dL (serum total bilirubin 0.79 mg/dL) and culture was positive for Escherichia coli, the same bacteria previously found in gallbladder drainage. The previous antibiotics regimen was administered and drainage rate diminished over 2 weeks. It is highlight that there`s possibility of cholethorax mimicking parapneumonic effusion when treating patients with previous PTGBD.