When the wheel-type sand washing machine is working, the motor drives the impeller to rotate slowly after being decelerated by the V-belt, the reducer, and the gear. At the same time, add water to form a strong water flow, take away impurities and foreign matter with a small specific gravity in time, and discharge them from the washing tank at the overflow port to complete the cleaning function. The clean gravel is taken away by the blades and poured into the discharge chute from the rotating impeller to complete the cleaning of the gravel.