The purpose of this study was to identify the relationships among critical thinking disposition, professional self-concept and clinical competence in nursing students. The participants were 291 nursing students in Gwangju Province. A questionnaire survey was conducted from March 02 to 16, 2013. Data were analyzed using descriptive statistics, t-test, ANOVA, Scheffe test, pearson's correlation coefficients, and stepwise multiple regression analysis with SPSS/WIN 20.0 version. There was a significant positive correlations among critical thinking disposition, professional self-concept, and clinical competence. The variable predicting clinical competency were professional self-concept and critical thinking disposition. These factors accounted for 44.1% of the variance. The findings of this study suggest that the most influential factor for clinical competence was professional self-concept. Therefore it is necessary to improve professional self-concept through effective education program.