The invention provides a drum washing
machine and a control method thereof. The drum washing
machine comprises an inner drum, an inner drum drainage port and a
resonance drainage device, wherein the inner drum is provided with a washing chamber capable of independently containing washing water; the inner drum drainage port is formed in the inner drum; and the
resonance drainage device is installedon the inner drum drainage port to keep the inner drum drainage port in a normally-
closed state, and when the rotating speed of the inner drum exceeds a certain value, the
resonance drainage device opens the inner drum drainage port. According to the drum washing
machine, the resonance drainage device is adopted to control on-off of the inner drum drainage port, the resonance drainage device utilizes the working principle of the washing machine, in the washing or rinsing stage, the rotating speed of the inner drum is low, resonance is not likely to happen to the resonance drainage device, andthe resonance drainage device keeps the inner drum drainage port in a normally-
closed state, so that washing water is independently contained in the inner drum in the washing stage and the rinsing stage; and when drainage or
dehydration is needed, the inner drum is controlled to rotate at a high speed, the resonance drainage device resonates to do
reciprocating motion, the inner drum drainage port is opened in the
reciprocating motion process, and drainage of the inner drum is achieved.