The purpose of this study is to examine the effects of teacher efficacy and teachers' attitudes toward inclusive education for children with disabilities on the emotional distress of middle school teachers in Japan. A survey of 95 middle school teachers in Yamaguchi Prefecture, Japan measured the attitudes of regular and special education teachers toward inclusive education and teacher efficacy in inclusive education. Then, this study assessed the impact of these factors on teachers' emotional distress. The results indicated that teachers' emotional distress was significantly and negatively correlated with high teacher efficacy in inclusive instruction and collaboration. Furthermore, teachers' emotional distress was significantly and negatively correlated with attitudes toward integrated classroom management. A regression analysis was performed, which further confirmed that middle school teachers' level of efficacy in inclusive instruction and attitudes toward integrated classroom management were unique predictors of their emotional distress. These findings provide further insights into the challenges facing middle school teachers involved in special needs education.