A door frame is provided with a first fixed portion and a second fixed portion to which one end and the other end of a beltline reinforcement, with respect to the lengthwise direction thereof, are fixed, respectively; the first fixed portion is provided with a lengthwise-direction position limit portion which is positioned on an extension of the beltline reinforcement in the lengthwise direction thereof and faces against the one end of the beltline reinforcement, the second fixed portion is provided with a thickness directional position limit portion which overlaps the other end of the beltline reinforcement in the door thickness direction, and the lengthwise-direction position limit portion and the thickness directional position limit portion are fixed to the corresponding ends of the beltline reinforcement by welding.