The utility model provides a portable car washing device, includes the pump body, water receptacle, carwash brush, power plug and dc speed regulation ware, power plug passes through the power port that the pump body is connected to the dc speed regulation ware, and the water receptacle is connected to the water inlet of the pump body, and the carwash brush is connected to the delivery port. When using, be connected power plug with the power output port on the automobile body, the direct current self priming pump gets electricly, holds the carwash brush, washs the automobile body through the carwash brush, as required, adjust the dc speed regulation ware for it reduces or increases to go out the water pressure. The utility model discloses simple structure can conveniently realize the cleanness of automobile body, and the cost is lower, the dc speed regulation ware that sets up has made things convenient for the adjustment that the water pressure, and design comparison is humanized.