The solid oxide fuel cell, Ni-YSZ cermet \ YSZ \ Au, could supply the stable electric power in an uniform atmosphere, namely, a mcthane + air mixture. At operating temperature of 950-degrees-C, the electromotive force (EMF) was 350 mV, and the terminal voltage was 159 mV at 14.7 mA cm-2 with 2.36 mW cm-2. The working mechanism of the fuel cell was based on the difference in catalytic activity for partial oxidation of methane between Ni-YSZ cermet and Au electrode materials.