A biochemical characterization and study of the biological activities of the aerial parts of Artemisia campestris was carried out. A. campestris is a plant belonging to the family of Asteraceae, growing spontaneously, widespread in North Africa, particularly in Tunisia, it is used in traditional medicine as anti-inflammatory, antioxidant and for the treatment of coetaneous pathologies. They contain powerful active compounds that vary from plant to plant and depending on how the chemicals have been extracted. A critical step in the preparation of antioxidant plant extracts is the selection the extraction solvent. This work proposes to evaluate the effect of extraction solvent on the phytochemical composition, antioxidant and antimicrobial activity of A. campestris. Three solvents (ethanol, methanol and water) were selected to perform this screening. Antioxidant activity was determined using 2,2-diphenuyl-1-picrylhyrazyl (DPPH) free radical scavenging ability, and ferric reducing antioxidant power (FRAP) assays. Antimicrobial activity was evaluated by disk diffusion and bacterial count assays.