The invention discloses an improved wheel alignment device which comprises a rack, a cylinder, a servo motor, a hollow shaft and the like. When the improved wheel alignment device is used, a stopper on a roller table centers a wheel, air enters at the lower end of a large piston and causes a long cylinder rod, a flange end cover, an expanding sleeve and the like to rise; the flange end cover is in contact with a wheel flange plate, and after the expanding sleeve is in contact with a central hole, air enters at the upper end of a small piston of a small cylinder, a short cylinder rod pulls an expanding core downwards, and the expanding sleeve clamps the central hole of the wheel; the servo motor causes the hollow shaft and the wheel to rotate by a belt pulley I and a belt pulley II, and the hollow shaft and the wheel stop rotating after a sensor finds the position of a valve hole of the wheel; at the moment, lifting cylinders cause a supporting plate to rise to a certain height through guide pillars, and a large cylinder causes the wheel to descend and the lower end surface of the wheel to fall above the supporting plate. The improved wheel alignment device can realize the alignment function before the automatic machining of wheel finish turning in use, and when the wheels with different wheel widths and different offset distances are automatically produced, programs do not need to be switched.