A stabilized NiO cathode was proposed and evaluated for the reduction of NiO dissolution in molten carbonate fuel cells. The NiO cathode was stabilized by the addition of alkaline earth oxide to the cathode. The solubilities of NiO and stabilized NiO in alkali metal carbonate (62Li(2)CO(3)-38K(2)CO(3)) were measured as a function of temperature, pCO(2) and pO(2). The MgO content in the stabilized NiO cathode was optimized with respect to its solubility. Half-cell and single-cell tests were also performed to evaluate the electrochemical performance of stabilized NiO cathode. In a long-run operation of single cell tests with a 10% MgO-stabilized cathode, a significant reduction of Ni precipitation was obtained.