To enable appropriate wafer mapping in the case where a wafer is stored at the highest level, which is provided as a reserve, of a pod, a load port apparatus drives a mapping frame that supports a sensor by a first driving unit that drives the mapping frame in a first direction parallel to the direction along which wafers in the pod are arranged in an overlapping manner and a second driving unit that drives the mapping frame in a second direction that crosses the first direction in such a way as to form an acute angle in the side in which the sensor starts the mapping.