Abstract: A photoelectric method of automatically controlling motion of a mining machine along a profile of a bed of a mineral deposit is described. A section of a face having at least two beds having different colors is illuminated. The reflected light flux is detected and the beds are distinguished by their colors. The boundary of the selected beds is tracked by identifying their color. The light flux reflected from each of said beds is converted into an electric signal by means of a photoelectric receiver. The direction of deviation of the mining machine with respect to the boundary of the selected beds is determined and the motion of the machine is corrected correspondingly. The device for effecting the proposed method includes a light source, an objective and a photoelectric receiver for conversion of the reflected light flux into electric signals. Located between the objective and the photoelectric receiver is a scanner unit for scanning the reflected light fluxes.