An electrolyte layer-anode composite member includes an anode including a first metal oxide having a perovskite crystal structure, and a solid electrolyte layer including a second metal oxide having a perovskite crystal structure, the anode including at least one of nickel and a nickel compound, the anode having a sheet-like shape, the solid electrolyte layer having a sheet-like shape, the solid electrolyte layer being stacked on the anode, the anode having a thickness Ta of 850 μm or more. The thickness Ta of the anode and a thickness Te of the solid electrolyte layer may satisfy a relation of 0.003≤Te/Ta≤0.036. The thickness Ta of the anode and a diameter Da of the anode may satisfy a relation of 55≤Ta/Da≤300.