This systematic review aims to identify, appraise, and synthesize empirical studies examining the fidelity of implementing the lower secondary vocational education curriculum in Tanzania. Curriculum fidelity is defined as the extent to which curriculum implementation aligns with the original curriculum design and intended objectives. The review focuses on evidence relating to threats to implementation fidelity, including factors associated with teacher capacity, resource availability, institutional support, and contextual conditions within Tanzanian secondary schools. In addition, the review synthesizes reported strategies and conditions that may enhance faithful and effective implementation of the vocational education curriculum. The review follows PRISMA 2020 guidelines to ensure transparency, reproducibility, and methodological rigor.