This quantitative, descriptive, correlational study sought to describe the nature of the relationship between the self-efficacy of school principals and their job satisfaction. The data were obtained from an online survey sent to all New Jersey public school principals. A total of 822 principals participated in the study. The independent variables included demographic characteristics of respondents and principal self-efficacy as measured by the Principal Self-Efficacy Scale (Tschannen-Moran & Gareis, 2004). The dependent variable was principal job satisfaction, as measured by the Minnesota Satisfaction Questionnaire Short-Form (Weiss, Dawis, England, & Lofquist, 1967). The analyses of the data were completed using simultaneous and hierarchical regression models and mediation analysis. The results indicated that principal self-efficacy is significantly and positively related to principal job satisfaction and partially mediates the relationship between select demographic characteristics of principals and their job satisfaction. The study revealed that a principal's self-efficacy level contributes significantly to his or her job satisfaction, a finding with implications for principal retention. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]