The content of polyphenols compounds in leaves in populations of red whortleberry (Vac- cinium vitis- idaea L.), bilberry (Vaccinium myrtillus L.) and bearberry (Arctostaphylos uva- ursi (L.) Sprengel) growing wild in Mazury and Podlasie were compared. *7 The highest content of arbutin and tannins was characteristic for bearberry leaves, the highest content of polyphenolic acids was characteristic for bilberry and flavonoids for red whortleberry. Significantly higher content of arbutin and tannins was characteristic for raw materials collected in autumn.