The aim of this work was to determine the diversity of qualitative humic substances in the ectohumus horizon of the forest soil profiles. The analyzed soils were located in protected landscape areas and nature parks – Bory Niemodlińskie and Lasy Stobrawsko-Turawskie, and occurred under the tree stands of trees which were 200-600 years old – Quercus robur. The analyzed soils represent 15 soil profiles belonging to Podzols, Cambisols and Dystric Cambisols. Properties of forest habitat specificity influenced the physicochemical and chemical properties of the analyzed soils. We observed particularly strong expressions of acidity, pH and salinity, and a diversity of chemical and optical properties of humic substances. The content of organic matter in the analyzed soil horizons showed considerable variation, as indicated by a coefficient of variation (V) equal to 61%. The composition of humic substances of forest litter is characterized by a gradual change of functional groups that usually consists in the decrease of carbohydrates, the relative increase of carboxyl and alkyl carbon, and decay of lignin. In the investigated soils, we observed that the transformation processes of organic matter led to humic substances which were predominantly humus with a lower level of humification, as evidenced by the indexes: A2/4, A2/6, A4/6, ∆logK. Therefore, variation of the observed properties of humic substances indicates a different direction in the transformation process of organic matter. Such a transformation depends very much on the habitat and nature of supplied organic matter.