The genus Equus comprises six species and 22 subspecies. Ethiopia is the only country in the world that has all three surviving species of zebra. The population status, structure, and seasonal range of Grevy's zebra (Equus grevyi) were studied in the Hallaydeghe Asebot Protected Area (HAPA), southeast Ethiopia, using line transects and silent detection methods. Data were collected from 2021 to 2022 covering both the wet and dry seasons. The seasonal range of Grevy's zebra was studied using the minimum convex polygon method. We counted 89 and 61 Grevy's zebra during the wet and dry seasons, respectively. The total population size was estimated to be 75 individuals with a 95% confidence interval of 60–90 individuals. The adult to sub-adult ratio was 3.1:1.0 during the wet season and 4:1 during the dry season. The sex ratio of adult female to adult male was 5:1 during the wet season and 4:1 during the dry season. The seasonal range of the species in the HAPA was 477 km² (n = 89) during the wet season and 711 km² (n = 61) during the dry season. During the dry season Grevy's zebra move out of the protected area to the Blen hot spring and its associated wetlands for green grazing and water. Hence, further study is needed on the possibility of incorporating the Blen hot spring and its associated wetlands into the protected area to promote the sustainable conservation of the species in the HAPA.