Ethnobotanical studies gather pure information that can be used to support scientific research. Traditional remedies are considered as an alternative tool to chemical treatments in health care. This study aims to investigate the knowledge of spontaneous medicinal plant used by healers and elderly people. Moreover, it focuses on consensus level estimation of used medicinal plants. An exhaustive survey was carried out in the region of Djelfa in Algeria. The information was gathered from 43 informants who responded to structured questionnaire. Survey data were quantitatively characterized by five indices, namely; relative frequency citation, medicinal use-value, family use-value, informant consensus factor and fidelity level. In the current study, 51 species belonging to 28 botanical families were recorded and 185 uses and 58 diseases were described as well. Most recipes used a single species; however, some preparations were used as a species mixture. This specific preparation is called "Djor yebrir" and it was used as a curative treatment. The most represented families were the Asteraceae, Lamiaceae, Cupressaceae and Poaceae. The most cited species were Artemisia campestris L., Juniperus phoeniceae L., Teucrium polium L., Marrubium deserti (Noë) Coss., Artemisia herba alba Asso., Ruta montana (L.) L. and Saccocalyx satureioides Coss. et Durieu. These species were mentioned to treat mainly digestive system diseases and signs and ill-defined morbid states which showed the highest consensus level. This study reveals that traditional remedies are still used in this region. This information showed the abundance of medicinal plants and the ethnobotanical knowledge in the studied region which need to be preserved, so phytochemical and biological screenings are more than needed.