We present a report of an extremely rare case of left main coronary artery atresia in a 33 year-old male with severe symptoms of angina pectoris and dyspnoea. During coronary angiography, the left coronary artery (LCA) ostium could not be catheterised. The right coronary artery (RCA) was dilated, and the LCA was filling retrogradely via collateral vessels. The diagnosis was confirmed by multislice computed tomography. Due to severe symptoms and the high risk of sudden cardiac death, the patient was referred for coronary artery revascularisation. The left internal mammary artery was anastomosed to the left anterior descending artery. The operation and subsequent 24 months follow-up were uneventful.