One-to three -month-old infants(n=252) were compared their growth performance(weight, length, head circumference, chest circumference) by feeding methods in cross-sectional study. There were two groups : breast-fed(BF) and formula-fed groups(FF). The weights of infants at 1, 2, and 3 postpartum month were 4.50+/-.48kg, 5.76+/-0.62kg and 6.67+/-0.68kg, respectively. The weigh of male infants was higher than females. The length were 53.7+/-2.6cm, 57.4+/-3.3cm, 61.1+/-3.1cm at one to three postpartum months, respectively. The length of male infants was higher than females, too. Overall there were no significant differences between feeding methods in weight, length, head and chest circumferences, and monthly weight and length velocity. But 3-month-old formula-fed male infants showed bigger significantly in weight, monthly weight velocity and chest circumference than the breast-feds. By Korean standards, weight-for-height Z-score were distributed from 0 to +2. Not only was there a few malnourished infants but also overnourished were noticed, especially in formula-fed group.