A store system includes a position information acquisition unit that acquires position information of an RFID medium attached to an item and position information of a visitor terminal carried by a visitor, an event detection unit that detects an event that the RFID medium or the visitor terminal enters or leaves a predetermined area in a store space based on the acquired position information, an event information storage unit that stores event information including an ID that identifies the RFID medium or the visitor terminal, information about the predetermined area based on the position information, and a detection time of the event, and a status determination unit that determines a status, which is a state of the item or is an action content of the visitor, based on the event information.