Purpose: The purpose of this study was to analyze the effects of professional self-concept and self-efficacy on job satisfaction and to identify the relationship among them in clinical nurses. Methods: The subjects were nurses who were working for three general hospitals in Seoul and Gangwon province for two month starting in July 2007. Three questionnaires were used. One was job satisfaction and the others were professional self-concept and self-efficacy. The data were analyzed by SPSS/PC ver 12.0. Results: The mean score of job satisfaction was 2.99 (range: 1-5). The mean score of professional self-concept and self-efficacy were 2.71(range: 1-4) and 3.49(range: 1-5), respectively. Differences of job satisfaction were significantly related to differences in age, marital status, level of education, clinical career, annual salary, and shift pattern. With respect to job satisfaction, the pearson correlation coefficients were .43 for professional self-concept and .29 for self-efficacy. The multiple regression revealed that the significant predictor of job satisfaction was professional self-concept. Conclusion: This study showed that a strong professional self-concept improves job satisfaction, so professional self-concept improvement programs should be developed to improve job satisfaction and to improve the quality of nursing.