The content of metals in carbonates, sulfides, exchangeable, adsorbed and organically bound forms was determined in bottom sediment by means of a sequential chemical extraction method after Rudd et al. Cadmium, nickel and copper was found mainly in the forms of sulfides (Cd > 40%, Ni > 30%, Cu > 70%), chromium and zinc in the fraction of carbonates and sulfides. Manganese was attributed to an organically bound form (25%), carbonates and sulfides. Iron had a very small contribution of the exchangeable and adsorbed forms (<1%); sulfides contributed the most (40-45%). Lead was found mainly in the fraction of carbonates (about 35%) at all sites. Aeration of the hypolimnetic water caused only slight changes in the forms of metal occurrence in the bottom sediment.