This study investigated the removal of sulfate, thiosulfate, and thiocyanate (SO₄^2- , S₂O₃^2- and SCN^-) by membrane capacitive deionization (MCDI) process. An electrochemical cell was fabricated using an anion exchange membrane and a cation exchange membrane placed on a carbon paper electrode, which operated as the anode and cathode. Batch mode experiments were conducted by recirculating single salt solutions of SO₄^2- , S₂O₃^2-, and SCN^- to determine the maximum removal efficiency. The anode electrode removed 8600 mg SO₄^2-, 9850 mg S₂O₃^2-, and 9350 mg SCN^- per m2 of the electrode. Batch mode experiments were also performed in mixed salt solution containing 100 mg/L SO₄^2-, S₂O₃^2-, and SCN^- to observe the effect of co-ions on the removal efficiency. In the adsorption phase, salt removal efficiency percentages were determined to be 57% for SO₄^2-, 57% for SCN-, and 88% for S₂O₃^2- at 1.2 V. In the desorption phase, the electrodes were regenerated by reversing the operating voltage to -5.0 V. The single-pass mode MCDI experiment showed that both S₂O₃^2-, and SCN^- were removed with a total salt removal of 539.6 mg/m² and 510 mg/m², respectively, during the adsorption phase. In the desorption phase, the removal rates increased to 719 mg/m² for S₂O₃^2- and 643 mg/m² for SCN^-, indicating the electro-oxidation of these ions.