The invention provides a sand washing machine. The sand washing machine comprises a sand washing pool, a supporting frame fixedly connected to the sand washing pool, a rotating wheel rotatably connected to the supporting frame and a motor driving the rotating wheel to rotate. The rotating wheel comprises a rotary shaft erected to the supporting frame, a circular screen mesh connected to the rotaryshaft through a supporting rod and a plurality of separation plates fixedly connected to the peripheral surface of the screen mesh and parallelly arranged in the circumferential direction, a plurality of screen plates are fixedly connected with the position between every two adjacent separation plates, first through holes are formed in the screen mesh, and second through holes are formed in the screen plates. According to the sand washing machine, the multiple separation plates and the screen plates are arranged, the first through holes are formed in the screen mesh, the second through holesare formed in the screen plates, therefore the screen mesh and the screen plates enable mud in sand to pass through when the rotating wheel rotates, sand washing is thorough, the sand washing efficiency is improved, and rework does not need to be conducted.