Purpose: The purpose of this study was to identify factors influencing parenting confidence in first-time mothers and to provide basic data for development of maternal role education programs. Method: The participants were 194 first-time mothers of babies aged 1-6 months who visited well-baby clinics in 4 hospitals. Instruments used in this study were self-reported questionnaires. The data were analyzed using descriptive statistics, Pearson correlation coefficient and stepwise multiple regression. Results: The parenting confidence level was moderate with a mean score of 3.26(range 1-6). Infant temperament was significantly correlated with maternal role confidence. Maternal role confidence was significantly correlated with child-rearing environment. Infant temperament and parenting stress were significant predictors explaining 50% maternal role confidence. Conclusions: Nursing Interventions to promote parenting confidence among first-time mothers of infants in their first year are needed to improve maternal perception to infant temperament and reduce parenting stress.