Hemp seeds are an excellent source of nutrients, such as essential amino acids and fatty acids, and their popularity is growing every day. They also contain bioactive molecules that function as antioxidants and therefore have a positive impact on human health. The aim of graduation thesis was to determine content of total phenolic compounds in different sorts of hemp seeds. We have also examined antioxidant potential (AOP) in different systems: homogeneous (ethanol) and heterogeneous (emulsion of linoleic acid in water) system. Before the extraction of phenolic compounds in 70 % ethanol, hemp seeds were grinded and defatted. We determined total phenolic content with Folin Ciocalteu method, analysed the scavenging activity of free DPPH• radicals and carried out ?-carotene bleaching assay in emulsion. We came to the conclusion that activity of particular antioxidant in homogeneous and heterogeneous system differentiates. Furthermore, hemp seeds with the highest content of phenolic compounds do not have the highest AOP.