The objective of the study was to evaluate the content of phenolic glycosides in bark of purple willow [Salix purpurea L.), originated from natural habitats. Special attention was paid to the soil features determining phenolic glycosides concentration in willow bark. The phenolic glycosides content in the purple willow ecotypes on peat soils was the highest (6.00%), whereas on alluvial soils (4.18%) and rendzina type (4.37%) was much lower. The content of phenolic glycosides in Salix purpurea bark in river valley habitats was determined by reaction and the content of Mg and CaC03