A drum washing machine includes a tub; a drum rotatably provided in the tub; an agitator rotatably provided in the drum and having a water spray hole; a driver in transmission connection with the drum via a main shaft, and the main shaft transmitting a torque of the driver to the drum; a planetary gear assembly in transmission connection with the main shaft and the agitator separately, and transmitting the torque of the main shaft to the agitator; a brake linked with the planetary gear assembly, and a water supply device configured to supply water to the agitator.