The invention relates to the field of washing protecting devices, in particular to a roller washing machine. The problem that an existing high-capacity washing machine is excessively large in boundary dimension and thickness particularly is solved. The roller washing machine comprises a box, a washing roller and a driving device, wherein the washing roller and the driving device are contained in the box. The roller washing machine is characterized in that the width of the box is larger than the thickness of the box; furthermore, a concave portion is arranged at the rear portion of the washing roller, and at least part of the driving device is contained inside the concave portion and directly connected with the washing roller for driving the washing roller to rotate. Due to the structural arrangement, the space inside the box is effectively saved, the size of the roller washing machine in the depth direction is decreased, the roller washing machine has the wide and ultrathin design effect, and the occupied space is greatly reduced.