The invention relates to a treatment and cleaning device for waste crystalline silicon, and particularly relates to an automatic acid/alkali cleaning reaction device for waste crystalline silicon. An acid/alkali sprayer is arranged in a reaction cleaning tank; a dredging conveyor is arranged in the tank; the dredging conveyor and a liquid surface upper end are provided with a cleaning sprayer and a jet port; the dredging conveyor conveys the material which is cleaned and subjected to impurity removal, out of the machine while carrying out blow drying on the material; a back flow port is arranged between the reaction cleaning tank and a filter tank; a liquid surface jet port is arranged at the position opposite to the back flow port in the reaction cleaning tank; a cleaning sprayer is also arranged in the reaction cleaning tank; when the material dredged by the dredging conveyor passes through the liquid surface, the liquid is sprayed to clean impurities on the material surface and also clean impurities floating on the surface in the position in contact with the dredging conveyor; and the upper part of the reaction cleaning tank is provided with a waste gas treatment and recovery device. The invention can efficiently treat waste crystalline silicon, and has a good cleaning effect.