The purpose of this research is to determine the effect of authentic leadership on trust in managers and schools' levels of openness to change. In the research, the convergent parallel method, one of the mixed design methods, was used. Correlational survey model was used in the quantitative part of the research. The qualitative part of the research was carried out in accordance with the case study. The participants of the quantitative part of the research are 668 teachers and the participants of the qualitative part are 18 teachers from 6 primary schools, 6 middle schools and 6 high schools. In the research, it was concluded that the authentic leadership behaviors displayed by school managers affected the trust in manager and the schools' openness to change positively and significantly, and the trust in manager affected the openness to change positively and significantly. In addition, ethical behaviors, being open in relationships, self-awareness, balanced processing and empathy skills ensure trust in the manager. It has been concluded that if the school manager exhibits authentic leadership behaviors, teachers' resistance to change decreases, and individual development, belief in change, sense of responsibility develop, their creativity develops, thus they are open to new ideas and they set new goals. Finally, it has been concluded that the trust in the manager helps teachers to show such behaviors as supporting the change, cooperating for change, complying with the determined vision and the rules and procedures created for change. In accordance with these results, suggestions such as giving seminars and in-service training explaining the effect of authentic leadership behaviors on change and trust have been presented to school managers.