Introduction. Propolis is a natural material whose extracts indicate numerous biological activities, including antifungal, antibacterial, antioxidant and anticancer. Phenolic compounds (flavonoids as well as phenolic acids and their esters) are one of the most frequently mentioned group of propolis components responsible for the biological activity of propolis extracts. Another group of components identified in propolis is elements, including macro- and microelements as well as heavy metals. Aim. The aim of the study was to determine the biological activity of the ethanolic propolis extract originated form Warmian-Masurian Voivodeship against moulds and to analyze concentration of selected flavonoids and elements present in the extract. Material and methods. The biological activity of the propolis extract obtained from a raw propolis originated from Warmian-Masurian Voivodeship against moulds was determined by dilution in nutrient solution. The content of selected flavonoids (apigenin, pinocembrin, kaempferol and galangin) in the propolis extract was determined using ultra-performance liquid chromatography photodiode array detection tandem mass spectrometric method. The concentration of elements in the propolis extract was analyzed by flame atomic absorption spectrometry. Results. The propolis extract was characterized by activity against all tested fungal strains. It showed the highest activity towards Chaetomium globosum and Penicillium cyclopium. Among analyzed flavonoids, the highest concentration in the propolis extract was determined for pinocembrin. In addition, high concentrations of Na, Mg, K, Ca and Fe were found in the propolis extract, and no toxic heavy metals were found. Conclusions. The ethanolic propolis extract of national origin shows biological activity against tested moulds and it is a valuable source of flavonoids, as well as macro- and microelements.