This study was carried out to determine the total amount of phenolic and flavonoid substances andantioxidant activities in Berberis vulgaris L. fruit extracts. Total phenolic and flavonoid substances weredetermined by using Folin-Ciocalteu and aluminum nitrate methods. The amount of phenolic substance in thehexane and methanol extract was determined as 33.64±1.86 mg GAE $g^{-1}$ and 85.98±1.59 mg of GAE $g^{-1}$ respectively, and the amount of flavonoid substance was determined as 94.74±2.59 mg QE $g^{-1}$ and 64.74±1.86mg QE $g^{-1}$ respectively. It was determined that DPPH• radical scavenging activities were higher in methanolextracts with a high amount of phenolic substances, while the reducing capacity of $Fe^{3+}-Fe^{2+}$ was higher inhexane extracts with a higher amount of flavonoid substances. According to the results we found, it wasconcluded that B. vulgaris can be considered as a food supplement and a source of natural antioxidants.