Abstract: A double ended ranging drum shearer is provided with a shearer body and a pair of drums disposed at front and rear end portions of the shearer body to be movable up- and down-wardly. The shearer is further equipped with detectors for respectively detecting the travelling position of the shearer body, detecting the inclination of the shearer body at the travelled position, and detecting the heights of drums at the travelled position. These detectors are operatively connected to a controlling device which is connected to a drum height adjusting device. The controlling device operates and stores the drum heights necessary for keeping constant the working height of a mining face in a pit in accordance with output signals generated from the abovementioned detectors, and the drum height adjusting device is operated in response to an output transmitted from the controlling device representing the thus operated and stored data.