Osteoporosis has been linked with arteriosclerotic vascular diseases, suggesting that hypercholesterolemia or dyslipidemia may be a common pathogenetic factor underlying these diseases. However, little is known about the relationship between osteoporosis and hypercholesterolemia. The purpose of this study was, therefore, to investigate the effects of hypercholesterolemia upon bone metabolism, by measuring bone turnover markers in hypercholesterolemic patients. This study included 281 Japanese patients with hypercholesterolemia, and 267 control subjects. Serum bone-specific alkaline phosphatase (BAP) of the patients was significantly higher than that of the controls in women. Serum N-terminal telopeptide of type I collagen (NTx) of the patients was significantly higher than that of the controls in both men and women. In addition, both BAP and NTx in men showed a significantly negative correlation with high density lipoprotein cholesterol (HDL-C). On the other hand, in women, both BAP and NTx showed a significantly positive correlation with total cholesterol and low density lipoprotein cholesterol (LDL-C). These results indicate increased bone turnover in hypercholesterolemic or dyslipidemic patients regardless of gender, and suggest the importance of treating hypercholesterolemia or dyslipidemia in order to prevent not only arteriosclerotic complications but also osteoporotic bone loss and subsequent fractures.