The invention discloses a tail wheel leaked coal cleaning device, relates to a cleaning device for leaked coal between a tail wheel and a bottom belt of a coal mine underground belt conveyor, and belongs to the field of mining machines. A screw conveying rod is located on the surface of a right-angled baffle, support plates are welded to the two sides of the right-angled baffle, the screw conveying rod is in tangency with the inner surface of the right-angled baffle, support shafts at the two ends of the screw conveying rod are located in support holes in the support plates, and bearings are arranged in the support holes; in the using process, the leaked coal between the tail wheel and the bottom belt of the belt conveyor can be automatically cleaned, and the leaked coal is conveyed to oneside of the belt through the screw conveying rod and the right-angled baffle and finally flows out of the surface of the belt; the whole process is started automatically after the belt conveyor is started, no manual participation is required, automatic cleaning is realized, and power comes from rotation of the tail wheel and is simple, reliable and easy to obtain; and the device is simple in overall manufacturing process and has the great promotion value.