Central venous catheterization is associated with a large number of complications, such as pneumothorax, hydrothorax, hemothorax, phlebothrombosis, pericardial tamponade, air embolism, aberrant placement and line sepsis. There are many case reports of the extravasation of various central venous catheter fluids, including the intravenous fluids, total parenteral nutrition and chemotherapeutic agents into the pleural cavity and mediastinum. These have led to hydrothorax, hydromediastinum and pericardial effusions. We report a case of the extravasation of intravenous contrast into the pleural cavity after dynamic CT through a left subclavian catheter.