A hydrogen generating apparatus having a fuel feeding part, a water feeding part for fuel reforming, an oxidant gas feeding part, a reforming catalyst body, a heating part for the reforming catalyst, a CO shifting catalyst body and a CO purification catalyst body is provided wherein the reforming catalyst body, the CO shifting catalyst body and the CO purification catalyst body are sequentially ordered from the fuel feeding part toward the downstream side, and wherein a shifting catalyst of the shifting catalyst body contains as one component at least a platinum group-type catalyst. A fuel and water are fed to the reforming part which has been heated, and an oxidant gas from the oxidant gas feeding part is nixed with each of a reformed gas introduced into the shifting part and a shifted gas obtained in the shifting part and introduced into the purification part, wherein at least a part of the reformed gas and at least a part of the shifted gas are oxidized, respectively, in the shifting part and the purification part.