The results of studies of humic substances and metals in rivers of the Pripyat’ river basin are discussed. It is shown that concentration of these natural organic compounds is within a wide range of values — from 8.9 to 167.7 mg/L (0.4–7.0 mmol C L−1). In river waters of the North Polessye it is above due to the predominance of peat and bog feeding in a forming of their runoff. In river waters of the Western Polesye the concentration of humic substances is in general much lower, but in some rivers it reaches approximately the same quantities as in the Northern Polesye. Humic substances are the predominant group of dissolved organic matter in studied river waters (73.3–88.3% C org). In the humic substance composition the high molecular compounds are dominated. The relative content of fractions with a molecular weight of 5.0–20.0 and > 20.0 kDa is 59.0–82.3% of the total concentration of humic substances. Prevalence of high molecular fraction of humic substances is reflected on their weight average molecular weight (M w), which is within 7.7–10.9 kDa. Humic substances in the high concentration have a significant influence on the behavior, migration and distribution of metals among their coexisting forms. In particular, the proportion of dissolved forms for such metals as iron and aluminum substantial increases because of complexation with humic substances which stabilize them in solution. Copper is found mainly as dissolved form due to complexation with humic substances. The close correlation between the content of titanium dissolved form and concentration of humic substances has not been established. The data on the distribution of metals among the complexes with dissolved organic substances of different chemical nature and also of anionic complexes with humic substances are given.