Manganese-doped C-60 fullerene films were produced on glassy carbon substrates by electrochemical reduction in aqueous solutions. It was established that manganese ions can be inserted into the fullerene lattice during the fullerene reduction initiated by potassium or sodium ions. The final reduced fullerene was mixed doped, containing either potassium and manganese, or sodium and manganese fulleride. The formation of manganese fulleride was explained by a mechanism involving ion exchange.