Manganese was removed from naturally polluted river sediment by applying an electrokinetic remediation technique. The sediment was alkaline and had 20% clay, which was mainly illite. The electrokinetic remediation experiments were performed by controlling pHs in the electrode cells and reverse electroosmotic flows were observed, i.e., water moved from cathode towards anode. Manganese accumulated in areas closer to cathode, however, other metals, such as copper, zinc and lead were mostly observed in the middle section of the sediment. As a result of reverse electroosmotic flow, the removal efficiencies of metals were low and the highest removal efficiencies of manganese, copper and lead, were evaluated as 18%, 20% and 12%, respectively. Almost no removal of zinc was observed in all electrokinetic remediation experiments.