The content of ions of the main salt composition and 50 dissolved trace elements (Li, Rb, Cs, Be, Sr, Ba, Mn, Fe, Co, Ni, Cu, Zn, Cd, Tl, Pb, Al, Sc, Ga, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ti, Zr, Hf, Th, U, F, B, Si, Ge, P, V, As, Sb, Cr, Se, Mo, W) in the waters of the Kolyma River mouth section the spring–summer flood decline and on the summer–autumn period was determined. A close positive correlation was established between the dissolved trace elements concentrations in the waters of the Kolyma River and of the rivers in the White and Kara seas catchment areas. Differences in the concentrations of dissolved trace elements in the river waters of the Russian Arctic are generally proportional to the ratio of their mineralization values.