The present research attempted to examine the relative importance of student-related and school-related factors in accounting for teacher efficacy in inclusive education. The research adopted a predictive research design, and the sample of the research consisted of teachers (N = 292) working in public middle schools in the province of Niğde in the Central Anatolia Region of Turkey. To determine the factors influencing teacher efficacy in inclusive education, Teacher Demographic Information Questionnaire and Teacher Efficacy for Inclusive Practices scale were used. In the research, multiple regression analysis was conducted to examine how well each set of independent variables — student-related factors and school-related factors — predicted teacher efficacy in inclusive education. According to the findings, student-related and school-related factors significantly influence teacher efficacy in inclusive education. Regarding the student-related factors, parental involvement, among other variables, was the most substantial predictor of teacher efficacy in inclusive education. Also, in terms of school-related factors, class size was the most substantial predictor of teacher efficacy in inclusive education.