This research was carried out to identify and document medicinal plants used by the people in Melga district of Sidama regional state for the treatment of both human and livestock ailments. The study employed both quantitative and qualitative methods. Data was gathered through semi structured-interviews, field observations, market survey and focus group discussions. For the interview a total 120 knowledgeable informants were sampled through purposive sampling method. Of which 20 key informants were identified with the help of elders and local administrators from the informants involved in the interviews. Preference ranking, Paired comparison, direct matrix ranking, Informant consensus factor and Fidelity level were used to quantify the collected ethno botanical data. A total of 84 medicinal plant species which belongs to 80 genera and 50 families were identified, with the Solanaceae being the most dominant one, and herbs, trees shrubs and climber constituting the largest types of plant habits, and natural vegetation and home garden being the source. Leaves were the most commonly used plant parts followed by root and seed; with crushing being the most dominant type of method for remedy preparation, followed by chewing and powdering, and oral routes being the most dominant type of drug administration, followed by dermal. Allium sativum was medicinal plant with higher informants’ consensus. The disease with higher ICF rate (0.90) was febrillness. Factors threatening traditional medicinal plants in the study area include agricultural expansion, fuel wood, overgrazing and overharvesting medicinal plants. Conservation of medicinal plants in home gardens, replanting, use of alternative source of energy, living fence and terracing were recommended to conserve and protect the areas that are used as a source of medicinal plant species.

Keywords: Ethnobotanical study, Human and livestock treatment, Medicinal plant, treatment, Melega district , quantitative and qualitative methods.