The present solution offers the method for isolating mercury from a solution, the solution containing metal and mercury salts being fed into the cathode chamber of an electrodialysis unit and its anode chamber, which is separated from the cathode chamber by an anion-permeable membrane, Electrolyte is fed. The solution is subjected to electrolysis, during which the transfer of the anions into the anode chamber causes the pH of the solution in the cathode chamber to rise to pH 8 8.5. From the solution prepared in this way, hydrated oxides and / or hydroxides of dissolved metals are excreted, to which the mercury salts, particularly complex mercury salts, then bind. The resulting suspension is discharged from the cathode chamber and subjected to filtration, with the recovery of filtrate and solid phase containing isolated mercury salts, whereupon at least part of the filtrate is discharged into the anode chamber as electrolyte.