One of the aims of this study was to examine the self-efficacy levels of school counselors, and the other was to test the mediating role of school climate in the relationship between self-efficacy and professional satisfaction. The study is a descriptive and correlational study. The participants of the study consisted of 561 school counselors. In the analysis of the data, arithmetic mean, standard deviation, t test, one-way analysis of variance and mediating effect analysis method were used. As a result of the research, it has been concluded that the general self-efficacy levels of school counselors are above the middle; and the self-efficacy levels according to the sub-dimensions are from high to low, Personal and Social Development, Collaboration, Leadership and Assessment, Career and Academic Development and Cultural Acceptance sub-dimensions. In addition, the self efficacy levels of school counselors who have more than 6 years of service, graduate degrees and working in private schools are significantly higher; it was determined that self efficacy did not differ in terms of gender, undergraduate program graduated, and education level. Finally, it was concluded that school climate has a partial mediator role in the relationship between self efficacy and professional satisfaction.