Academic optimism is a vital concept that can help schools overcome the challenges posed by students from low socioeconomic backgrounds. This study investigates the factors that influence the academic optimism of secondary school teachers. Using a phenomenological approach, we collected data through focus group interviews with principals and teachers, employing the maximum variation sampling technique to ensure diverse perspectives. Our analysis revealed three themes that affect teachers' academic optimism: self-efficacy, academic emphasis, and trust in students and parents. Notably, our findings indicate that teachers' experiences of success or failure are the most significant determinant of their academic optimism. Based on these results, we propose actionable strategies to enhance teachers' self-efficacy, ultimately promoting academic optimism in secondary schools.