The invention relates to an automatic water supplying steam washer. A water inlet magnetic valve, a storage water tank, an electromagnetic pump, a one-way valve, an electrical heating steam boiler, a steam magnetic valve and a steam nozzle are connected with each other sequentially; a temperature controller, a pressure controller, a safety valve and a high temperature electric water level device are connected with the electrical heating steam boiler separately; a normal temperature electric water level device is connected with the storage tank; a microcomputer controller is connected with the high temperature electric water level device, the normal temperature electric water level device, the pressure controller, the temperature controller, the electrical heating steam boiler, the electromagnetic pump, the steam magnetic valve and an operating panel separately; the steam nozzle is mounted on a shell body; the operating panel is embedded on the shell body. The automatic water supplying steam washer adopts the structure combining the small-size steam boiler, the storage tank and the automatic water supply system to continuously generate steam, and especially to automatic supply water in operation under the non-stop state, the automatic water supplying steam washer is small in size, low in heating efficiency, high in safety, short in preheating time and is more energy-saving as compared with the traditional boiler steam generator.