The invention provides an anti-collision method and device for a roller washing machine and the roller washing machine. The anti-collision method comprises the steps that a processing module obtains an acceleration, collected by a collection module, of a roller in the roller washing machine; the processing module calculates the displacement of the roller according to the acceleration, and judges whether the displacement of the roller is higher than a preset threshold or not; if yes, the processing module controls an electromagnetic module which is electrically connected with the processing module to be turned on, so that the electromagnetic module generates acting force which acts on the roller, and under the action of the acting force, the displacement of the roller is reduced to be lowerthan the preset threshold, wherein the direction of the acting force is opposite to the direction of the displacement of the roller. According to the anti-collision method, when it is detected that the displacement of the roller is higher than the preset threshold, an electromagnetic field generated by the electromagnetic module makes mutually repulsive counter-acting force generated between theroller and a tank, collision between the roller and the tank is avoided, deceleration is not needed, and it is not required that a dewatering process is re-enabled. The anti-collision roller is achieved under the conditions without wasting resources or affecting the dewatering efficiency.