Abstract: In this paper, a new type of water-saving washingmachine is designed with the centripetal force of the high-speed spinning tub of the auto washing machine beingused to draining water and the water being removed from clothes along the innerside of a tub. The major structural parameters as well as the major part, waterdrain valve, can be determined by the mechanical analysis for this new type ofauto-washing machine. This new type of auto-washing machine with simplestructure and large capacity may save both water and detergent.