The patient was a 74-year-old male. Before lung cancer surgery, during computed tomography (CT)-guided marking, the patient suddenly complained of dyspnea and suffered cardiopulmonary arrest. Cardiopulmonary resuscitation (CPR) was immediately initiated and cardiopulmonary arrest due to air embolism was diagnosed, based on retained air in the left atrium, left ventricle and ascending aorta during CT scan. Since the patient's status progressed to an intractable ventricular fibrillation, we initiated treatment with percutaneous cardiopulmonary support (PCPS) while continuing CPR in the CT laboratory and transferred him to intensive care, where the patient was placed in the Trendelenburg position and given defibrillation shock therapy, which restored spontaneous circulation. Transesophageal echocardiography 4 hours after the onset showed retained air in the ascending aorta and left atrium; emergency thoracotomy was thus performed to remove this air. We confirmed air elimination with transesophageal echocardiography intraoperatively and discontinued PCPS. Thereafter, general status improved and he was discharged without sequelae. We saved the life of a patient experiencing cardiopulmonary arrest due to air embolism, without sequelae, by using PCPS immediately while keeping his head down and removing the air surgically by emergency thoracotomy.