Species of the genus Globularia are a rich source of polyphenolic compounds, to which flavonoids also belong. It is known that these compounds have an antioxidative effect responsible for prevention of various diseases such as cancer and cardiovascular diseases. In this thesis, flavonoid content and antioxidative effect in vitro of different species from the genus Globularia: G. alypum, G. cordifolia, G. meridionalis and G. punctata were compared. Therefore, four different extraction methods were used for the preparation of samples: decoction, ultrasound extraction, maceration and acid maceration. Flavonoid content was determined with aluminium chloride colorimetric method, where quercetin served as the standard substance. Antioxidative effect was determined by using the DPPH test, where the standard substances used were Trolox and gallic acid. Obtained results show that the highest flavonoid content is present in samples that were prepared by decoction. Flavonoid content was highest in G. punctata (11.69 ± 0.07 mg quercetin equivalent/g dry plant material). By comparing the results of all extraction methods, it was noticed that G. punctata was richest in flavonoids. The results of the DPPH test show that extracts obtained by decoction have the highest antioxidative effect. Decoct of G. meridionalis had the highest antioxidative effect (51.98 ± 8.08 mg Trolox equivalent/g dry plant material; 10.03 ± 1.52 mg gallic acid equivalent/g dry plant material). Extracts of G. meridionalis prepared by ultrasound extraction also showed the highest antioxidant effect in comparison to extracts of other species prepared with the same method, while in the method of maceration they have shown lowest antioxidative effect. The highest antioxidative effect of samples prepared by maceration was observed for G. alypum extract.