For wildlife management and conservation biology, it is important to be able to estimate the status and distribution of animals and to monitor their population trends. In the Etosha National Park, Namibia, there is a lack of knowledge about numbers and distribution of spotted hyenas (Crocuta crocuta (Erxleben, 1777)) and factors regulating their population. To estimate hyena density and distribution, tape-recorded vocalizations (call-ups) were performed to attract hyenas in the central and eastern parts of Etosha. Eighty-five adult and subadult hyenas responded to the calls, with most of them responding in an area with high density of migratory ungulates, principally springbok (Antidorcas marsupialis (Zimmermann, 1780)), wildebeest (Connochaetes taurinus (Burchell, 1823)), and Burchell’s zebra (Equus burchelli (Gray, 1824)). These migratory species are the main prey of spotted hyenas in Etosha. There was a strong spatial relationship between hyena density and migratory prey biomass. Based on this mathematical correlation, I estimated 203 ± 79 hyenas, i.e., 2.7 ± 1.1 hyenas/100 km², in the central and eastern parts of Etosha. Applying this correlation to the western part of the park, it was possible to estimate 339 ± 176 spotted hyenas, corresponding to an overall density of 2.1 ± 1.0 hyenas/100 km², in the whole Etosha National Park.