It has been well established that raloxifene (RLX) has beneficial effects on bone primarily in Caucasian women. However, to date, there is a dearth of data for Japanese postmenopausal women. In this study, we prospectively evaluated the effects of RLX on bone and lipid metabolism in fifty Japanese postmenopausal patients with untreated osteoporosis. We measured bone mineral density (BMD) by dual-energy X-ray absorptiometry at 7 sites including the lumbar spine, femoral neck, and distal radius. BMD was significantly increased at the lumbar spine both at 6 months and at 12 months compared with at baseline (p<0.01 for both), although the possibility could not be completely excluded that this increase may be partly explained by an apparent increase induced by degenerative changes in lumbar vertebrae since we had no control subjects to compare and be more certain of the findings in this study. Both bone-specific alkaline phosphatase (BAP) and serum N-terminal telopeptide of type I collagen (NTx) significantly decreased both at 6 months (p<0.01 for both) and at 12 months (p<0.01 for both) compared with at baseline, but not below the lower limit of the reference value. Total cholesterol and low-density lipoprotein cholesterol were significantly improved while triglycerides and high-density lipoprotein cholesterol were unaltered. Although longer and larger studies with fracture endpoints are needed to draw definite conclusions, our findings suggest the favorable effects of RLX on bone and lipid metabolism in Japanese postmenopausal women with osteoporosis as in Caucasian women.