Actuality. Metals excessive concentrations reduce biomass of plants in ecosystem. Trace elements effect on biotic systems as biochemical agents, breaking the ultrastructure of cells, physiological processes and metabolism of plants, affect the species composition, reproduction and recovery processes, productivity and resistance to pathogens. As the plants mainly define the environment of ecosystem, the determination of phytotoxicological risk plays an important role in ecosystem assessment. In large cities, natural ecosystems are confined to park areas. Goloseyevsko-Feofanivska and Koncha-Zaspivska green parks are very popular in Kyiv. Phytotoxicological assessment of the metals behavior risk in natural ecosystems is based primarily on classification principles. The phytotoxicological classification should be considered in two aspects. The first aspect concerns the metals toxicity for plants. The second aspect concerns the plants reaction to metals concentration in phytomass. Analysis of recent research and publications. According to the opinion of many scientists, species and families of plants differ in chemistry, and only due to the lack of research in this direction have to be limited in the classification of their morphological features. There are no classifications of metals and plants according to concentration in phytomass. Studies concerning the phytotoxicity of metals or the sensitivity (or the opposite of resistance) of certain types of plants to metallic pollution are non-systemic and relate solely to physiological aspects. The purpose of the study was to rank metals and plants by metals concentration in the phytomass in natural ecosystems of Goloseevo-Feofanivska and Koncha-Zaspivska green zones of Kyiv. Materials and methods of research . Goloseyevsky-Feofanivska and Koncha-Zaspivska green areas of Kyiv are part of the landscape of elevated hilly-sloping plains on the Paleogene-neogene basis, composed of forest sanded loams. Thanks to convex relief and loamy soils, studied areas have intensive removing of elements, in particular, anthropogenic pollutants. Both studied parks are located at the junction of the Right-bank Polissya and the Forest-Steppe zones of Ukraine in warm medium-tempered agro-climatic zone. The content of Cd, Co, Cu, Pb, Ni, Pb in the phytomass was analyzed in: Gagea lutea L., Tussilago farfara L., Anemone ranunculoides L., Ficaria verna Huds., Pulmonaria obscura Dum., Stellaria holostea L., Convallaria majalis L., Hypericum perforatum L.. The photosynthetic fraction of the phytomasses of the first and second tier of the trees was analyzed in: Quercus robur L., Carpinus betulus L., Salix caprea L., Tilia cordata Mill., Acer platanoids L.; Trees of the third tier: Sambucus nigra L., Prunus padus L.. Results and discution . The phytotoxicological classification of metals (Cd, Pb, Ni, Co, Zn, Cu) was developed for their concentration in phytomass. According to the Stargess equation, the metals were ranged in four dangerous classes. The middle arithmetic mean of each metal concentration in plants was used for calculation the scope of the metal’s dangerous class. The highest level of phytomass concentration in plants had copper, the lowest concentration in plants had cadmium and cobalt. Zinc as a physiologically important trace elements, and lead, whose physiological role is not thoroughly investigated, are both were in the middle phytotoxicological class. The middle arithmetic mean of metals concentration in each plant was used for calculation the scope plant class. Plants with low and moderate metals concentration in phytomass were: Carpinus betulus L. , Acer platanoides L. , Quercus robur L ., Prunus padus L. , Salix caprea L ., Tilia cordata Mill. , Sambucus nigra L. . Plants with high metals concentration in phytomass were: Tussilago farfara L ., Anemone ranunculoides L. . Highest metal concentration among the trees was in Goloseevka green park area near Goloseevsky Avenue. In our researches we tried to zoning the studied area according to metals concentration in trees. With helps of Fisher’s criteria the difference between trees concentration in different zones of studied areas was highlighted. The Ghoryhuvatska locality was characterized as most polluted zone than others in studied area. More pollution obviously could be explained by proximity to highway Goloseevsky Avenue. Conclusions and perspectives . The phytotoxicological classification of metals and phytotoxicological classification of plants were proposed for metals risk assessment in nature ecosystems. For the first time the algorithm of the metals ranking for the four danger classes according to metals concentration in phytomass was proposed. There were ranged all studied plants due to metals concentration in their phytomass. Assignment the metals and plants to phytotoxicological classes will allow not just only to characterize the hazard of metals for plants, but to detect the reaction of plants to metals influence in nature ecosystems.