To understand the abundance, distribution, and population trends of the common hippopotamus (Hippopotamus amphibius) in the Gonarezhou National Park (GNP), Zimbabwe, we (i) carried out an aerial survey along sections of major perennial rivers, namely Runde, Save and Mwenezi and other inland water pans, and (ii) analysed the long-term aerial survey data (1965-2008). For the aerial survey, a Piper PA-18 Super Cub aircraft was flown once along each of the three major rivers and associated pans in November 2008. We recorded a total of 187 hippos and 19 groups in the GNP. All sightings were in Runde River, Tambohata Pan and Massasanya Dam (density = 2.4 hippos/km). We found three trends in hippo populations in the GNP for the period 1965-2008. Keywords: Aerial survey, Drought, Hippopotamus amphibius, Large herbivores, Siltation, Southeastern lowveld, Gonarezhou National Park, Bindura University of Science Education.