The objective of this thesis was to determine the antioxidative properties of the polyphenol preparations obtained from the seed coats of broad bean (‘Windsor Biały’ and ‘Bartom’). The preparations were prepared by extracting polyphenols using a 0.5% HCl solution in methanol, condensing them under the vacuum conditions, and lyophilizing them. In order to provide a chemical profile of the preparations obtained, the content of total polyphenols, condensed tannins, and anthocyanins were determined. While determining the antioxidative properties of the polyphenol preparations, their capacities to deactivate stable, synthetic DPPH^• radicals and hydroxyl radicals were identified and estimated. Additionally, the ability of the preparations produced to chelate the ions of iron II was studied. It was found that the preparations studied exhibited antiradical activity both against the DPPH^• radicals (65-70%) and the hydroxyl radicals (48-50%). The preparations investigated also chelated the ions of iron (II). The preparation extracted from Windsor Biały was characterized by a stronger antiradical activity, and this could be probably caused by the higher content of polyphenols in this preparation.