This research is to study about the weight-change of a pregnant woman, conditions of the woman and an infant. The weight-change of a mother during pregnancy was observed and that was expressed as the basis on the body mass index of a mother before pregnancy. The effects of weight-changes on both the discomfort, complications of pregnant mother and the condition of an infant were also investigated. Thus we set a purpose that this study would help pregnant woman and an infant to maintain and enhance their health conditions by proper weight control through nursing mediation. This study was performed in a certain hospital of university in seoul from Feb. 1. 2000 to Mar. 31. 2000. We explained the purpose of this study to the hospital institution and obtained consent of investigation. 152 inpatients who were in condition from PA 37 weeks to PA 42 weeks were the subject of this study. The research materials were made through of question paper that inpatients make answer by themselves and investigation paper. The question paper was about general background, weight and height before pregnancy and discomfort of the physical degree. And the investigation paper was about parity, maternal weight(late pregnancy), high pregnancy, delivery method, hemoglobin level, Apgar score, fetal weight. Physical discomfort was measured using the implement made by Kim hae won(1996) (chronbach's ${\alpha}=0.85$). SPSS was used to do statistics for managing and analyzing data. The results of this study were like followings. 1. The mean value of gained weight during pregnancy was about 13.8kg within from 3 kg to 26 kg. Among 152 research candidates, the gained weight of 80(52.6%) candidates remained within an ideal range. But that of 37 candidates(24.3%) became less than the ideal range. Also that of 35 candidates(23.0%) became over than the ideal range. 2. In the investigation of the relation between the weight change of a pregnant woman and her condition, the scores to represent physical discomfort were middle in all candidates. And the physical discomfort of over weight-gained group was more than that of low weight-gained group, but there was no difference in statistics(F=0.234, p=0.791). The weight-changes of pregnant woman didn't have an influence with the high risk of pregnancy(F=0.509, p=0.477). Also, the weight-changes didn't have an influence on delivery method($x^2=3.825$, p=0.148). However, in the investigation of the relation between weight-change and hemoglobin level, the change of hemoglobin level was highest in over weight gained group(F=3.062, p=0.05). 3. In the investigation of the weight-change of pregnant woman and the condition of infant. the weight changes didn't have an influence on both 1 min Apgar score(F=0.157, p=0.855) and 5 min Apgar score(F=0.030, p=0.970) of infant. Also, in the investigation of weight-change of a pregnant woman and weight difference of a infant with Pearson Correlation Coefficient, the weight-change of a pregnant woman affected vastly the weight of a infant. It was also found that the more pregnant woman gained in weight, the more did gain weighty infants. This relation was in net proportion(r=0.256, p=0.001). In conclusion, these results suggest that the weight-changes during pregnancy in Korea women of these days are more increased than that of the past days and individual variation in weight-changes is very high. Also, these results suggest that the changed hemoglobin level of a mother and weight of an infant were meaningfully affected by the weight-changes of a pregnant woman during pregnancy. However, the physical discomfort of a pregnant woman, the high risks of pregnancy, the delivery method and Apgar score of an infant were not affected by the weight-changes during pregnancy. Because the recommendation suggesting the ideal weight-change, used this study, is basis on the subject of American women, therefore, these results also suggest the necessity of such recommendation which is subject to Korean women.