Information on animal diversity and distribution is essential for designing management plans for conservation. This study aimed to investigate primate diversity and species' distributions in the Maze National Park, southern Ethiopia. The study was conducted during the dry season (January–March) and wet season (June–August) in 2020. Fourteen line transects in four stratified habitats were followed, and 613 individual primates belonging to three species [olive baboon Papio anubis (Lesson, 1827), mantled guereza Colobus guereza (Rüppell, 1835), and vervet monkey Chlorocebus pygerythrus (F. Cuvier, 1821)] were identified. Papio anubis was the most frequently observed primate species in both the dry and wet season in the riverine forest (n = 99 and n = 97, respectively) and in woodland (n = 43 and n = 40, respectively), whereas fewer C. pygerythrus were observed in the riverine forest in both seasons (n = 38 and n = 34 in the dry and wet season, respectively). The highest numbers of primates were recorded in the wet and dry season in the riverine forest (n = 194 and n = 204, respectively), followed by woodland (n = 78 and n = 80, respectively), open grassland (n = 10 and n = 17, respectively), and wooded grassland (n = 8 and n = 18, respectively). During the dry season, the riverine forest habitat had the highest diversity index (H′ = 1.25). These findings will be useful for the urgent prioritisation of primate conservation programmes in the park.