The invention relates to a method for verifying the calibration status of an optical tracking system (1), wherein: a calibration apparatus (20, 40), which comprises a tracking marker configuration (27, 28; 41, 42), is moved to within the detection range of the tracking system (1); the tracking markers (27, 28; 41, 42) of the calibration apparatus (20, 40) are detected by the tracking system; the arrangement of the tracking markers (27, 28; 41, 42) is changed and/or moved into a state such that the tracking system (1) experiences a detection problem; the arrangement of the tracking markers (27, 28; 41, 42) which causes the detection problem is gauged and/or a range of arrangements for the tracking markers (27, 28; 41, 42) which causes the detection problem is gauged; and the tracking system (1) is determined to have a calibration error when the gauged arrangement and/or range of arrangements does not have a predetermined value or is not within a predetermined range of values. It also relates to a device for verifying the calibration status of an optical tracking system (1).