The invention relates to a twin-tub washing machine. The washing machine comprises a control panel, a box body, twin tubs, a control system and a transmission system. The washing machine is characterized in that an open topped water box device is installed on the control panel; the control panel of the twin-tub washing machine is provided with a cavity which is provided with an upward opening and is used for containing the water box device at the side of a wash tub; the water box device comprises a water box top cover with a water filling hole, a water distribution panel and a washing powder box; the water distribution panel is provided with water leakage holes; and the area of the water distribution panel region on which the water leakage holes are arranged is larger than the area of the region used for containing the washing powder, of the washing powder box. The twin-tub washing machine has the following beneficial effects: the water filling water box can realize the double functions of filling water and putting washing powder and is simple to install and convenient to operate; and the inlet water flow is uniform and can wash all the washing powder into the wash tub, so the washing machine is more humanized to use.