This study was performed to examine the relationship between the body mass index (BMI), the body fat, and the serum lipids of post-menopausal women in rural areas. The subjects were 510 women aged 50 and over. As a result of this study, we found a trend of decreasing BMI as age increased, but body fat increased. In addition, there was a significant decreasing of the lean body mass than an increasing of the body mass index according to increasing age. Therefore, this study confirmed that a main cause of rural women being classified as obese is a decrease in lean body mass, rather than an increase in of body fat. Of all subjects, 36.3% ($18.5{leq}BMI$ < 23) of all subjects were classified as having normal BMI, whereas only 21.4% were classified as having normal body fat. Out of 190 subjects who were body fat 30% and over, 38 subjects were classified as obese ($BMI{geq}25$) and 113 subjects were classified as overweight ($23{leq}BMI$ < 25). The percentile of those with a BMI of $25kg/m^2$ was 70, and they had 30.82% body fat. HDL cholesterol showed a negative correlation with anthropometric factors (height, weight, body mass index, waist circumference, waist hip ratio, body fat), and total cholesterol, LDL cholesterol, and triglycerides showed a positive correlation. Especially, total cholesterol, LDL cholesterol, and hip circumference showed significant correlations. Because of differences in the body fat and lean body mass by age group, it seems difficult to assess obesity via BMI only. The elderly especially should have a higher significance placed on body fat or abdominal fat than only BMI.