This study investigates the relationships among teacher self-efficacy, grit, metacognition, and work engagement among secondary school English as a Foreign Language (EFL) teachers in mainland China and Hong Kong. Utilizing a purposive sampling method, 592 teachers from diverse educational settings participated in the study. Structural Equation Modeling (SEM) was employed to analyze the data, revealing that both self-efficacy and grit significantly predict work engagement, with teaching metacognition serving as a mediator in these relationships. Notably, the impact of self-efficacy on work engagement was stronger in Hong Kong, while grit exhibited a more pronounced indirect effect through metacognition in the same region. These findings underscore the importance of fostering self-efficacy and grit, alongside enhancing metacognitive practices, to bolster teacher engagement. The study highlights cultural and systemic factors that influence these dynamics, providing insights for developing targeted professional development programs and supportive educational policies tailored to different cultural contexts.