Subject:To study the relationship of Body Mass Index with the body composing and fat distribution.Method:The body composing of 188 candidates was measured with Hologic QDR 4500W Dual-energy X-ray absorptiometry.The data about body composing such as fat,lean,bone mineral,the percentage of trunk fat and the ratio of trunk fat to whole body substance composing were studied,and the data about body height and weight also were measured to be used to calculate the body mass index(BMI).