A method of manufacturing an outer joint member of a constant velocity universal joint, the outer joint member being constructed by forming, through use of separate members, a cup section having track grooves formed at an inner periphery of the cup section and engageable with torque transmitting elements (19,41), and a shaft section formed at a bottom portion of the cup section, and by welding a cup member forming the cup section and a shaft member forming the shaft section, the method comprising: forming the cup member and the shaft member of medium carbon steel; preparing, as the cup member, a cup member having a cylindrical portion (12a1) and a bottom portion (12a2) integrally formed by forging, and a joining end surface formed on an outer surface of the bottom portion (12a2) in a machining step after the forging; and being characterized by the following steps: preparing, as the shaft member, a shaft member having a joining end surface to be joined to the bottom portion (12a2) of the cup member, which is formed in the machining step, and a bearing mounting surface and a snap ring groove, which are formed at an outer periphery of the shaft member; bringing the joining end surface of the cup member and the joining end surface of the shaft member into abutment against each other; and welding the cup member and the shaft member by radiating a beam from an outer side of the cup member to an abutment portion between the cup member and the shaft member in a radial direction of the cup member, wherein the joining end surface of the shaft member is located at the position on the cup member side with respect to the bearing mounting surface, and the joining end surface of the cup member and the joining end surface of the shaft member having a dimension difference between outer diameters thereof. forming the cup member and the shaft member of medium carbon steel; preparing, as the cup member, a cup member having a cylindrical portion (12a1) and a bottom portion (12a2) integrally formed by forging, and a joining end surface formed on an outer surface of the bottom portion (12a2) in a machining step after the forging; and being characterized by the following steps: preparing, as the shaft member, a shaft member having a joining end surface to be joined to the bottom portion (12a2) of the cup member, which is formed in the machining step, and a bearing mounting surface and a snap ring groove, which are formed at an outer periphery of the shaft member; bringing the joining end surface of the cup member and the joining end surface of the shaft member into abutment against each other; and welding the cup member and the shaft member by radiating a beam from an outer side of the cup member to an abutment portion between the cup member and the shaft member in a radial direction of the cup member, wherein preparing, as the shaft member, a shaft member having a joining end surface to be joined to the bottom portion (12a2) of the cup member, which is formed in the machining step, and a bearing mounting surface and a snap ring groove, which are formed at an outer periphery of the shaft member; bringing the joining end surface of the cup member and the joining end surface of the shaft member into abutment against each other; and welding the cup member and the shaft member by radiating a beam from an outer side of the cup member to an abutment portion between the cup member and the shaft member in a radial direction of the cup member, wherein the joining end surface of the shaft member is located at the position on the cup member side with respect to the bearing mounting surface, and the joining end surface of the cup member and the joining end surface of the shaft member having a dimension difference between outer diameters thereof.