The article deals with the regularities of accumulating of heavy metals and biologically active agents (photosynthesis pigments) in inundated types of meadow plants. Research was conducted in four plant communities: a mixed herbs-cereal shrubby meadow, a mixed-herbs-canary shrubby meadow, an aspen forest shrubby meadow, an osier-bed sedge in the neighborhood of the village of Yugan, Surgut District, Khanty-Mansiysk Autonomous Area - Yugra. Collection of plants was made for determination of the content of photosynthetic pigments (chlorophylls a, b , carotinoids) and heavy metals on the trial areas. 7 types of plants served as an object of our research: Calamagrostis purpurea (Trin.) Trin., Carex acuta L., Carex aquatilis Wahlenb., Carex vesicaria L., Carex rostrata Stokes., Elytrigia repens (L.) Desv. ex Nevski, Phalaroides arundinacea (L.) Rausch . In plant communities we conducted the sampling of the studied plants (roots, leaves) and also soil sampling was made. Roots of plants were cleared from soil and washed in flowing water. Samples were selected 5 times. Experiments were conducted on the dried-up raw materials. The freshly-gathered plants cleared and washed from soil were also sterilized in the laboratory from foreign impurities, they were dried up and weighed on electronic scales. The mobile form of elements in soil and vegetable samples were kept by an atomic and absorbing method. Determination of pigments of photosynthesis (chlorophyll and carotinoids) in solid of plants was carried out by spectral and photometric method. An electrometric method was applied for determination of рН in salt and water extract of the soil. During the working progress we revealed that the content of heavy metals in roots of meadow plants is 3 times more than in leaves. Specific features concerning absorption of heavy metals by plants and their adaptations to environmental factors appeared. Negative influence of a high concentration of lead and cadmium on the content of pigments of photosynthesis in leaves of sedge was revealed, whereas copper influence was generally positive. All the studied inundated meadow types of plants (Carex rostrata, Carex acuta, Elytrigia repens, Phalaroides arundinacea, Carex aquatilis, Calamagrostis purpurea, Carex vesicaria) showed the coefficient of absorption less than 1 in relation to copper and lead which demonstrates availability of a biochemical barrier, especially in relation to lead. However sedges actively absorb toxic cadmium, the coefficient of biological absorption is often more than 1. The acquired results can be used in bioindication of oil pollution, and also during the study of production processes of meadow plant communities.