A map information update system includes a map database; a server; a vehicle position recognition unit configured to recognizes a vehicle position of a vehicle on a map; an external environment information generation unit configured to generate external environment information related to an external environment of the vehicle in association with the vehicle position on the map based on the vehicle position on the map and a detection result of a sensor mounted on the vehicle; a map freshness calculation unit configured to calculate map freshness per area set in advance on map information; a awarding unit configured to award a user of the vehicle or the vehicle an incentive point which is set in advance in accordance with the map freshness of the area corresponding to the external environment information, when the external environment information is transmitted to the server from the vehicle; and a user interaction unit.