A walker straight moving wheel assembly comprises a wheel support and a wheel thereof, the wheel support is provided with a brake component, the brake component is movably connected with the wheel support, a rotating shaft is arranged between the brake component and the wheel support, the rotating shaft sequentially penetrates through the wheel, the wheel support and the rotating shaft, and the brake component is limited to rotate on one side of the wheel support through the rotating shaft; the brake component comprises a brake frame, a mounting groove for mounting the brake frame is formed inthe bottom end of the wheel support, a through hole is formed in one side of the brake frame, mounting holes are formed in the two sides of the mounting groove of the wheel support, the brake frame is inserted into the mounting groove, and the rotating shaft penetrates through the mounting holes and the through hole. The wheel support is provided with the brake component, the brake component directly acts on the wheel, the wheel is effectively braked by changing the direction of the brake component in the wheel support, and the state of the wheel on the wheel support is changed.