The main object of the present study was to investigate the impact of different drying methods (shade, lyophilazation, oven, solar drayer) on the antioxidant and antibacterial activities of Oudneya africana (spontaneous medicinal plants) in the Northern Algerian Sahara. The experiments were based on draying the leaves by four different methods (in the shade, oven (45°C.), solar dryer and lyophilization). The fresh plants were used as control. The extract was performed by using cold maceration with mixture of 70% methanol and 30% distilled water. Lastly, the different extracts were used to evaluate their biological activities. Our results showed that lyophilization and solar drayer were the better modes for preserving the antioxidant activity of Oudneya africana extracts where the EC50 value was 0.333 mg/ml. Furthermore, the four studied bacterial strains (Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Micrococcus luteus) showed a low resistance against Oudneya africana extracts dried by a solar dryer and lyophilization.