Algeria, a country renownes for its natural resources, has a singularly rich and diverse flora. The main objective of this study was to assess phytochemical composition, antioxydant activity and antimicrobial properties of five selected medicinal plants from Khenchela region, east of Algeria. Phytochemical tests revealed that M. vulgare, A. campestris and Z. lotus hydroethanolic extracts possess the most promising phytochemical profile, due to their significantly high levels of phytoconstituents. Colorimetric assays showed polyphenol and flavonoid contents rangin from 57.4 +/- 0.02 µg GAE/mg 145.89 +/- 0.39 µg GAE/mg E, and from 10.05 +/- 0.02 µg QE/mg E to 33.42 +/- 0.2 µg QE/mg E, respectively. Antioxydant activity was evaluated using DPPH scavenging assay. The results revealed that M. sylvestris exhibited a potent antioxydant capacity with an IC50 OF 2.29 +/-0.5 mg/ ml. Antimicrobial activity was assessed in vitro using the agar diffusion method. The results showed S. aureus was highly sensitive, with inhibition zone diameters of 22 mm, 12.3+/- 1 mm and 11mm for Z. lotus, A. campestris and C. spinosa, respectively. A moderate sensitivity was observed for other Gram positive and Gram negative strains with all extracts. However, they were be inactive against Aspergillus niger. The majority of selected plants exhibited notable bioactivity, which can be attributed to the presence of different classes of secondary metabolites. These results offer scientific support for the traditional medicinal use of these species.