A device and a method for controlling a two-cylinder thick matter pump to achieve a reliable operation even of single-circuit two-cylinder thick matter pumps. To this end, the pipe switch includes a position transmitter responding to the pivoting position. At least two cylinder switching sensors are arranged on the working cylinders at a distance from each other, responding to the passing pistons of the drive cylinder, and/or a pressure sensor responding to the pressure course at the high-pressure outlet of the reversible pump is provided. A computer-assisted reversing device has a control routine responding to output signals of the position transmitter and to output signals of the cylinder switching sensors and/or the pressure sensors, enabling the programmed control of a control body for adjusting the flow quantity and direction of the reversible pump, and a reversing element arranged in the hydraulic branch of the pipe switch.