A track jump control apparatus for a disc reproducing system having a transport unit for moving a pickup element that reads data recorded on the disc in the radial direction of the disc at a high speed. The system also has a detecting unit for detecting a moving direction of the pickup element unit based on a pick-up signal output from the pickup element while the pickup element moves in the radial direction of the disc, and a protection unit for stopping the pickup element moved by the transport unit when the pickup element is judged to be moving in a different direction from the direction moved by the transport unit. The apparatus has a measuring unit for measuring a pulse duration of the picked-up signal, which is continuously obtained from the pickup element while the pickup element moves in the radial direction of the disc at a high speed. The apparatus also has a control unit for inverting a detected result of the detecting unit when the pulse duration of the picked-up signal is beyond a specific limit based on the measured result of the measuring unit.