An increase in the culturally and linguistically diverse student population in the United States requires teachers to prepare to meet students’ needs in the changing classroom. Teachers with low self-efficacy beliefs lack the confidence to bridge cultural divides in classrooms and provide rigorous educational opportunities for culturally and linguistically diverse students. A literature gap exists concerning culturally responsive teaching self-efficacy beliefs among certified middle school teachers. The purpose of the qualitative phenomenological study was to describe certified middle school teachers’ culturally responsive teaching self-efficacy beliefs, exploring teachers’ experiences and perceptions of personal abilities to rigorously teach culturally diverse students. Study questions explored culturally responsive teaching self-efficacy beliefs of certified middle school teachers; lived experiences, which influence teachers’ beliefs in the ability to implement culturally responsive teaching in culturally diverse classrooms; and teachers’ greatest successes and challenges in implementing culturally responsive teaching. An analysis of 15 teacher interviews and a four-member focus group were conducted using structural and lean coding. Results revealed teachers hold high self-efficacy beliefs regarding maintaining cultural awareness, building student relationships, and providing vocabulary instruction to address test bias. Descriptions of low self-efficacy beliefs involved teachers’ perceived ability to integrate students’ cultural backgrounds into instruction and to overcome language barriers when communicating with English language learners and parents. Limitations, recommendations, and implications for leadership were discussed.