The aim of the present work was to study the distribution of 210Ро cationic forms in lichen thalli by alpha-spectrometry. Five samples were used for experiments. By sequential extraction technique 4 210Po-containing fractions was extracted from every sample: intercellular, extracellular, intracellular and insoluble residue. It was found that the uptake of 210Po by investigated lichens is carried out mainly as a passive process: up to 12% of 210Ро transfers into fraction 1, up to 35% - into fraction 2 and up to 72% - into fraction 4. Active absorption of 210Po is reflected by fractions 3, which contain from 3 to 12% of the radionuclide. It was found out that on average the amount of 210Po in fraction 3 is 3 times higher in cell cytoplasm of terricolous lichens than of corticolous lichens. We concluded that 210Ро comes into corticolous and terricolous lichens as the different chemical substances and therefore has various biological availability.