Gas-tight Y2O3-stabilized ZrO2 (YSZ) films were prepared on NiO-YSZ and NiO-SDC (Sm0.2Ce0.8O1.9) anode substrates by a novel method. A cell, Ni-YSZ/YSZ(10 mu m)/LSM-YSZ, was tested with humidified hydrogen as fuel and ambient air as oxidant. The maximum power densities of 1.64, 1.40, 1.06, and 0.60 W/cm(2) were obtained at 850 degrees, 800 degrees, 750 degrees, and 700 degrees C, respectively. With methane as fuel, a cell of Ni-SDC/YSZ (12 mu m)/LSM-YSZ exhibited the maximum power densities of 1.14, 0.82, 0.49, and 0.28 W/cm(2) at 850 degrees, 800 degrees, 750 degrees, and 700 degrees C, respectively. The impedance results showed that the performance of the cell was controlled by the electrode polarization rather than the resistance of YSZ electrolyte film.