Abstract: A washing machine and washing method thereof comprises an inner tub, an outer tub and solid particles as washing medium. The inner tub, of which the inner wall is provided with lifting ribs protruding inward, rotates under the driving power of a driving device. Inside the washing machine, a storage tank for storing particles connects to the inner tub through a discharge channel for recycling particles and a feeding channel for putting in particles, and an air suction device is arranged on the feeding channel. Through alternate clockwise and counter-clockwise rotates of the inner tub, clothes and particles within are overturned in all directions, thus clothes and particles get better blended, and the cleaning rate gets improved. Meanwhile, putting-in and recycling particles through an air suction device is conducive to 100% recycling of particles.