Purpose: The purpose of this study was examine levels of breastfeeding knowledge, attitude and number of breastfeeding problems in early postpartum period and rate of breastfeeding practice at 3 months. Method: The total numbers of the study subjects were 139 mothers at postpartum unit and followed by postpartum 1 week and 3 months. Result: 1. The mean score of knowledge and attitude and problems toward breast feeding scale were 22.83(SD=5.19), 20.99(SD=3.40), and 9.04(SD=3.59) respectively, indicating low to moderate level according to subjects characteristics, breastfeeding knowledge scores were significantly different by age (F=8.00, p<.001), breastfeeding experience (t=3.26, p<.001) and parity(t=2.39, p<.05), but no difference were found in rate of breastfeeding attitude and number of problems. 2. Rate of breastfeeding practice was 46.5% at three months of postpartum and the breastfeeding practice was significantly different by breastfeeding plan period($x^2$=13.33, p<.001) and monthly income ($x^2$= 3.80, p<.05). 3. Further, breastfeeding practice at 3 months was continuously influenced by number of problems of the breast-feeding(OR=.85) and breastfeeding plan period(OR=2.11) at early postpartum period. Conclusion: The findings suggest the necessity of maternal support during postpartum period to provide correct information about rate of breastfeeding knowledge and attitude to teach problem solving skills for any breastfeeding problems in order to increase rate of breastfeeding practice.