Objectives: To compare the body composition of the postpartal female weight-gained over the recommended during pregnancy with that of normal female with same age, female diagnosed as obesity and postpartal female weight-gained within the recommended during pregnancy. Methods: From Apr. 1. 2001 to Feb. 28. 2002, there were 745 delivery in Dept. of Obstetrics & Gynecology, Kyung-Hee Medical Center. 32 mothers of them wanted to be investigated about the weight gain during their pregnancy. We excluded 12 persons who had gained within the recommended weight(15㎏) and had diagnosed as the diseases inducing pathologic edema, preeclamsia, gestational heart or renal diseases, for example. In 2 days after delivery(nomal) or 5 days after(Caesarean section) we analysed the body composition of 20 persons. Results: 1. Compared with normal female, body weight, body mass index and body fat of the women gained over the recommended were increased and there made alternation to the increase of the percentage of body fat or the decrease of the percentage of lean body mass. 2. Compared with obese women who had same body mass index, the women gained over the recommended showed a little increase of body fluid, protein and mineral, but had a little decrease of the percentage of body fat. 3. The percentages of body fat increased with the women gained over the recommended, the women gained within the recommended and the obese women in order. This could imply the relation between the pregnancy, weight gain during pregnancy and the obesity. 4. The weights before pregnancy were same in the women gained over the recommended and the women gained within the recommended. But the weights just after delivery kept the gap happened during pregnancy between them and its main cause was the increase of body fat.