A walking assist device has a frame, fixed handles, rails provided with movable handles, front wheels, rear wheels and that serve as drive wheels, drive units, a battery, and a drive control unit, and travels forward or rearward together with a user that walks while grasping the fixed handles or the movable handles. The walking assist device has an operation mode switching unit that switches between a training mode, in which a load is applied to operation of the body of the user performed as the user walks, and an assist mode in which a load on operation of the body of the user performed as the user walks is alleviated.