The invention relates to a measurement device for a laser processing system, for carrying out position measurements by means of a measurement beam on a workpiece, which is intended for processing by means of a high energy processing beam, which can be moved relative to the workpiece along a predetermined main processing path. The measurement device can be coupled to a processing device and includes an optical coherence tomograph. The measurement device is equipped to shift the measurement beam on the workpiece in the direction of the main processing path in at least one first measurement position and one second measurement position in order to scan measurement positions transversely to the direction of the main processing path in the measurement positions.