Studies on sorption of heavy metal ions (Cr2+, Cu2+, Cd2+ and Zn2+) onto peats of defined type, sort, and kind, as a function of their physical and chemical properties, as well as de­ter­mi­nation of adsorbent-adsorbate binding stability have been carried out. Among the tested peats the best sorption properties have been found for low-moor peats: Humus Peat and Rush Peat, characterized by high decomposition rates (DR). Among studied heavy metals, the greatest chemical affinity to sorption sites showed chromium ions, bound onto organic matter in insoluble forms, the lowest - zinc and cadmium ions, which mostly enriched mobile forms.