Because the complications of decreased bone mineral density, such as femoral neck fractures and severe spinal deformities, have a strong impact on daily life, prevention has become more important than therapy. The present study included as subjects 771 women residing in Innoshima City, Sera-gun, and Mihara City, all in Hiroshima Prefecture. We determined bone mineral density in the lumbar spine and femoral neck of these women, measured their height and weight, and examined the effect of age and body mass index (BMI) on bone density rate (YAM%). The subjects of the study were all volunteers. As no significant difference could be demonstrated in comparison with the results of the 1998 National Nutrition Survey of height, body weight, and BMI, we considered there would be no problem in extrapolating the results of the present determinations to middle-aged and elderly women. In the relationship between age and YAM%, a negative trend was observed prior to menopause, but was not significant. After menopause, however, a significant negative correlation was demonstrated. In addition, a significant positive correlation was observed between BMI and age-corrected YAM% for the lumbar spine and femoral neck. In future studies, the YAM% of the lumbar spine and femoral neck corrected for age and BMI should be investigated to determine the influence of lifestyle.