Relevance. The necessity of a wide analysis of the mechanisms of binding radioactive and rare-earth elements with different chemical behavior to dissolved organic matter for an accurate assessment of their mobility in the environment. Aim. To determine the fluorescent components of peat dissolved organic matter using PARAFAC analysis and establish the strength of elemental bonds to peat organic matter. Methods. Chemical group composition analysis for peat, gamma spectrometry, spectrophotometry, fluorescence spectroscopy, PARAFAC component analysis, inductively coupled plasma mass spectrometry. Results and conclusions. The authors have studied the group chemical composition of the peat deposit Petropavlovskiy Ryam along the profile. It was found that the content of humic acids, bitumen, cellulose, and peat ash content increases with depth growth. The authors studied distribution of anthropogenic radionuclides in peat depending on the depth. It was found that the maximum of cesium-137 and americium-241 is concentrated in the layer of 20–30 cm, and the maximum activity of plutonium-239,240 occurs in the layer of 10–20 cm. The optical properties of peat dissolved organic matter were determined depending on its depth and solution pH, on the basis of which it was possible to evaluate the features of the structure of organic compounds of the humic part of peat. Using PARAFAC factor analysis the authors determined the main components of peat – fulvic and humic acids, the content of fulvic acids prevails over humic acids 1.5 times at pH 3–12, and 1.7–2 times at pH 0.5–2.5. The spatial distribution of rare-earth elements and Th, U along the profile of the top layer of peat was studied and their affinity to organic fractions was established. Thorium forms the strongest complexes with humic acids (70–80% binding), uranium binding with humic acids was 30–40%, rare earth elements – 20–37%.