The invention provides a screw shaft structure of a bottle washer. The screw shaft structure effectively prevents corrosion of a bearing, improves the service life of the bearing and ensures normal use of the bottle washer. The screw shaft structure comprises a screw shaft arranged in a cleaning water tank; and one end of the screw shaft is connected with a drive device, wherein the screw shaft structure is characterized in that the other end of the screw shaft is supported and arranged outside the cleaning water tank through the bearing, and the screw shaft is in sealed connection with the cleaning water tank.