Science syllabuses, standardized examinations, and teacher content knowledge are critical to the development of scientific literacy. In this study, we quantify the presence of biological evolution in the Caribbean Secondary Examinations Certificate (CSEC) biology syllabus and examinations as well as evaluate the level of evolutionary knowledge held by teachers in the country of Belize. Analyses of the biology syllabus (2002) and the 2005–2012 examinations suggest that biological evolution plays a minimal role at the secondary level in the Caribbean. Evolution is limited to Section C of the syllabus, where it focuses on natural selection and genetic engineering but omits key microevolutionary and macroevolutionary processes. Of the 96 structured/extended essay questions that formed part of the 2005–2012 examinations, 26 were classified as Evolutionary Questions (EQs), while 70 were classified as non-evolutionary questions (NEQs). With a mean knowledge score of 47.9%, Belizean teachers were classified as having a “Low Understanding” of biological evolution. Teachers knew the least about macroevolutionary concepts such as speciation, fossils, and extinction and had several misconceptions regarding key microevolutionary concepts such as natural selection. The results of this study highlight the need to: (1) revise the CSEC biology syllabus to reflect the importance of evolution and its interrelationships within biology, and (2) provide professional development programmes to address teachers’ lack of knowledge of basic concepts in biological evolution.