A survey was conducted in Hamer and Benna-Tsemay districts of the South Omo zone of Ethiopia, with the objectives of assessing the range-livestock management practices and perceptions of the different pastoral groups (Hamer, Benna, and Tsemay) towards rangeland degradation. This information is considered to be vital to future pastoral development planning and interventions. The information was gathered through group discussions, personal observations, and using a structured questionnaire where each household was taken as a unit of analysis. The average family size per household was for Hamer = 7.05 for Benna = 7.93 and for Tsemay = 7 with nearly 98.1% of the respondents without any kind of education. All pastoral groups derived their main income from the sale of animals, which was followed by the sale of honey as in the case of Hamer and Tsemay pastoralists. The average livestock per household was 25.7, 10 and 2.8 tropical livestock unit (TLU) cattle, goat and sheep, respectively. The major livestock production constraints were drought, feed and water shortage and animal health problems. The different pastoral groups have the opinion that the condition of their rangeland is poor, mainly due to overgrazing, drought and increase in human population. Furthermore, there was also a problem of bush encroachment which is an indicator of rangeland degradation. There are no range improvement practices undertaken to improve the condition of the rangelands. Mobility is the first measure taken to solve shortage of livestock feed and water but many of the pastoralists replied that they face many problems during migrations. Because of the unfavorable climatic condition for cultivation, most of the respondents of Hamer and Tsemay pastoralists and about 35% from Benna still prefer communal land tenure, where resources are shared. In conclusion, the indigenous knowledge of the pastoralists about range-livestock management and their environment should be incorporated while planning range-livestock development projects for the study districts.