Workpiece transport system and workpiece transport method

A workpiece transport system, comprising:

• a mounting pedestal on which a workpiece can be mounted;
• and
• a workpiece holding robot configured to be able to transport, from the mounting pedestal, the workpiece mounted on the mounting pedestal,
• the workpiece holding robot including a workpiece holding portion capable of holding the workpiece, an arm unit configured to bring the workpiece holding portion close to or away from a detection target, and a surface detection sensor capable of detecting that the workpiece holding portion is brought into contact with the detection target,
• the workpiece transport system being configured to detect a height error of the workpiece holding portion based on a height from a mounting pedestal side floor surface, on which the mounting pedestal is mounted, to a connection point between the workpiece holding portion and the arm unit at a point in time at which contact with the detection target is detected by the surface detection sensor, a height from the mounting pedestal side floor surface to a surface of the detection target, and a theoretical value of a height of the workpiece holding portion, and to detect an actual loading height of the workpiece mounted on the mounting pedestal in consideration of the height error of the workpiece holding portion.