This study to study and analyze the current state of infancy breast-feeding & practice and related factors and to provide basic data for the effective practice of breast-feeding and breast-feeding percentage improvement. For the object, 474 mothers of the infants who were born between Jan. 1, 1998 and Dec. 31, 1998 were selected, and the survey period & method were from Oct. 15, 1999 through Nov. 14, 1999 (1 month period) and telephone interview, respectively. To examine by month breast-feeding type, the average breast-feeding percentage in 1 month after a child's birth was 42.4%, but after 6 month it decreased to 23.0%. To see breast-feeding percentage by academic background, the breast-feeding of elementary school graduated mothers was 33.3%, which was highest, and it decreased as the academic background of mothers went better (p〈0.01). By employment state, the percentage for the mothers who were not employed was higher (24.6%) than that of those who were employed at the time, which was 8.0% (p〈0.001). There was no meaningful difference found in breast-feeding percentage by infant mothers age, delivery place, infant sex, child order in family, weight at the time of birth. To examine breast-feeding percentage by delivery method, natural delivery was 27.0% which was higher than 13.1% of Caesarean section (p〈0.01), and by breast-feeding experience before leaving the hospital, 35.6% of those who have breast-fed were breast-feeding while it was 16.4% for those who never did it while in the hospital (p〈0.001). After conducting logistics multi return analysis having breast-feeding percentage as a variable at the time of 6 months after babys birth, I found that infant mothers employment state, delivery method, and breast-feeding experience before leaving the hospital become meaningful variables. As unemployed mothers (p〈0.05), as chose natural delivery (p〈0.05), as experienced breast-feeding before leaving the hospital (p〈0.001), there was more tendency to do breast-feeding. Summing the above results, I would like to suggest the following to raise breast-feeding percentage. Firstly, systematic education about the importance and advantages of breast-feeding and correct breast-feeding method should be practised for women. Secondly, vacation before and after childbirth for working women should be practised and the support of systems for working womens breast-feeding such as installation of nursery in work place are needed. Thirdly, continuous publicity and education for natural delivery inducement is necessary, and for the ones who chose Caesarean section, recommendation of breast-feeding is also needed. Fourth, for breast-feeding within fastest time after delivery, rooming-in required and legal and systematic support is also needed. Lastly, in the governmental level, publicity for breast-feeding and breast-feeding recommending programs that promotes 10 rules for successful breast-feeding bringing-up, provided by UNISEF and WHO, are to be provided.