The increase in the age of patients undergoing operations has become more prominent in recent years. We report our experience of minimally invasive cardiac surgery-coronary artery bypass grafting (MICS-CABG) by left small intercostal thoracotomy for very elderly patients. Case 1:The patient was a 91-year-old woman with a history of percutaneous coronary intervention (PCI) for left anterior descending artery (LAD) and right coronary arteries at different timings. Due to her contrast media allergy, we performed MICS-CABG to treat 75% stenosis of LAD. Blood transfusion was not required. She was discharged on the 13th day. Case 2:The patient was a 92-year-old man. We performed MICS-CABG for 75% stenosis of the left main trunk and 90~99% stenosis of the LAD with severe calcification. Blood transfusion was not required. He was discharged on the 21th day. MICS-CABG can be performed with less invasiveness in comparison to the conventional method and therefore seems to be an effective method of surgery for very elderly patients.