The effect of microwave-assisted extraction (MAE) process on the antioxidant capacity/activity of three medicinal herbs from Turkey was investigated by electrochemical differential pulse voltammetric (DPV)CUPric Reducing Antioxidant Capacity (CUPRAC) assay. The optimal extraction time, temperature and solvent type were 6 min, 80 degrees C and 80% (v/v) methanol (MeOH), respectively. Microwave-assisted extracts of herbs (Hypericum scabrum L., Papaver fugax Poiret var. platydiscus Cullen, and Achillea vermicularis Trin.) were screened for total antioxidant capacity (TAC), total phenolic content (TPC) and ROS scavenging activities by employing different in vitro spectrophotometric assays. A positive correlation was observed between TACCUPRAC and TPC (R-2 = 0.972). Similarly, a positive correlation was observed between TAC-CUPRAC and free radical scavenging (FRS) activity (R-2 = 0.977). The order of FRS activities of tested samples was as follows: Hypericum scabrum L. > Achillea vermicularis Trin. > Papaver fugax Poiret var. platydiscus Cullen. These results suggest that these medicinal herbs provide promising antioxidant potentials as potential natural preservative agents in pharmaceutical industries.