The paper presents the outcomes of a examine of the interplay of heavy metallic cations Fe3+, Cr3+, Cu2+, Pb2+, Zn2+, Ni2+, Ag+ with carbon dots synthesized by the hydrothermal methodology in water. It was discovered that each one the studied cations quench the fluorescence of nanoparticles to 1 diploma or one other. The collection of cations have been decided in line with the diploma of their affect on the fluorescence of carbon dots. The mechanisms of quenching the fluorescence of carbon dots upon interplay with cations have been investigated. It’s proven that the quenching of the luminescence of nanoparticles within the presence of the investigated cations of heavy metals has a fancy character. The noticed adjustments within the depth of fluorescence of carbon dots are the results of a superposition of a number of components—electrostatic interactions of metallic cations with floor fluorophores of carbon dots, aggregation of nanoparticles, and the impact of an inside filter for iron ions.