The invention discloses an ash removal device comprising an ash bucket, a fly ash reburning pipe, and an electric ash discharge valve; an arc separator is arranged in middle of the ash bucket; an ash inlet/outlet is connected with a flue; an ash bucket inlet and an outlet are different in width; the ash removal device can effectively separate mass fly ashes in the flue gas, is obvious in ash removing effect, thus reducing flue gas purifying cost, and fly ash reburning can effectively improve boiler heat efficiency; the ash removal device is compact in structure, convenient in mounting maintenance, and suitable for ash bucket arrangement of a vertical type garbage burning boiler.