Cardiovascular complications were examined in a 31-year-old woman with homozygous familial hypercholesterolemia (FH) (LDL receptor defective type), who had had no clinical symptoms of coronary artery disease. She had delivered 2 children without any cardiac complications, and her exercise electrocardiogram showed no positive findings for ischemic heart disease. Coronary angiography showed no significant arterial lesions, and left ventriculography revealed good contraction of the left ventricle (ejection fraction: 67%). This is considered to be a very rare case of homozygous FH without significant lesions in the coronary arteries. This might be attributed at least in part to her dietary regimen consisting of a very low fat and low calorie diet, to the residual LDL receptor activity or to the low value of prothrombin time.