A turbine rotor includes a high- and low-temperature side rotor base materials. The high- and low-temperature materials include concavities and grooves. The turbine rotor has an enclosed space formed by the concavity of the high- and low-temperature materials being disposed opposingly, and a gap formed by the grooves of the high- and low-temperature materials being disposed opposingly. The turbine rotor contains a buildup welding section formed between the high- and low-temperature materials, which has the same composition as that of the high- or low-temperature material, and has a penetration bead on the enclosed space side, and the gap contains a weld metal filled therein. Thus, a stable penetration bead can be formed in a dissimilar material welded rotor combining two kinds of alloy materials with different thermal properties, and then generation of a non-welded portion of a butting section that becomes a start point of fracture can be suppressed.