The invention relates to a drying reduction method and device for excess sludge and provides a drying reduction method for the excess sludge. The method comprises the following steps: (A), physical extrusion for preliminary dewatering; (B), shearing and crushing of a sludge filter cake; (C), primary vortex autorotation dewatering of crushed sludge particles; (D), vibrating drying of the sludge particles; (E), secondary vortex autorotation drying of the sludge particles after vibrating drying; (F), air-liquid separation of wet air. The invention also provides the drying reduction device for theexcess sludge.