A 57-year-old man underwent prone position computed tomography (CT) guided percutaneous transthoracic lung biopsy. After removal of the 18-gauge biopsy needle, the patient lost consciousness and developed shock. CT showed signs of air embolism in descending aorta and left atrium. Cardiopulmonary resuscitation was unsuccessful. A postmortem CT scan confirmed a massive air embolism in the descending aorta, left ventricle and brain. Systemic air embolism occurs in around 0.001–0.003% of lung biopsy procedures. Recommendations to reduce the risk include requesting the patient to stop breathing during the procedure and preventing the exposure of the outer cannula of a coaxial biopsy needle to the atmosphere.