Background.Arisarum vulgare is screened and its total phenolic compounds and total flavonoid contents were measured. In addition, the antioxidant capacity of the methanol-water (7:3) extract of this plant is evalu- ated by DPPH (2,2-diphenyl-1 picrylhydrazyl) and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfon- ic)) tests expressed by Vitamin C Equivalent Antioxidant Capacity (VCEAC). HPLC analyses are carried out to identify some polyphenols. The aim of this study is to identify, to quantify the phenolic compounds contained in the seeds of A. vulgare, and to evaluate their antioxidant capacity.Material and methods. Methanol-water (7:3) extract and three fraction obtained from silica gel column chromatography of A. vulgare were assayed by using RP-HPLC, spectrophotometric analyses, DPPH and ABTS tests.Results.Results obtained in the present study, revealed that total phenolic and flavonoids of methanol-water extract of A. vulgare seeds were respectively 1.2 g GAE and 0.34 g QE per 100 g of plant extract dry weight. The total antioxidant capacity expressed as vitamin C equivalent antioxidant capacity (VCEAC) per 100 g of plant extract, obtained by ABTS and DPPH tests were respectively 1.3 g and 0.99 g VCE per 100 g dry weight. On the other hand RP-HPLC analyses reveal that the main phenolic compounds identified in the methanol-water (7:3) extract are gallic acid, caffeic acid and rutin.Conclusions.The results reveal that the methanol-water extract of A. vulgare seeds possesses strong antioxi- dative properties in vitro. Results confirmed by high polyphenols and flavonoids contents and corroborated by HPLC identifications.