The present invention discloses an installation structure for a wheel axle assembly and a wheel fork, a frame and a vehicle. The wheel axle assembly includes a wheel axle; a first bearing, a bushing and a second wheel axle sleeved on the wheel axle successively; and a hub arranged on the outer rings of the first bearing and the second bearing, wherein the bushing is used for spacing apart the first bearing and the second bearing axially a predetermined distance, and the hub is of a sleeve shape and an end thereof arranged on the first bearing expands the outer diameter to form a flange portion for fixing and installing a wheel; and the wheel fork includes a wheel fork body and a frame connection portion formed on an end of the wheel fork body and forming an L shape with the wheel fork body for connecting to a frame, and the wheel axle is fixed on the other end of the wheel fork body in a direction perpendicular to the rim center plane of the wheel.