A 78-year-old man who was diagnosed as having hepatocellular carcinoma(segment 4/8)underwent laparoscopic hepatectomy. About 5 hours after the start of the operation, SpO2 and systolic blood pressure suddenly dropped to 87% and 40 mmHg. EtCO2 level decreased to 8 mmHg and PaCO2 was 48.5 mmHg. Based on the discrepancy between the PaCO2 and EtCO2, the patient was diagnosed as having pneumoperitoneum-induced carbon dioxide embolism. The surgical procedure was immediately interrupted and the patient was hyperventilated with pure oxygen. After surgical interruption, general status was recovered to the normal condition. We carefully restarted the operation and completed it laparoscopically. The patient was discharged from the hospital on the 15th day without any postoperative complications. Carbon dioxide embolization is a serious life-threatening complication that requires careful monitoring.