A map update determination system includes a traveling plan generation unit generating, based on a target route of a vehicle set in advance and map information, a traveling plan of the vehicle including a control target value for the vehicle in accordance with a position on the target route, a detection value acquisition unit acquiring, in association with the position on the target route, a control result detection value resulting from an automatic driving control for the vehicle executed based on a road environment in a vicinity of the vehicle, a traveling situation of the vehicle, a position of the vehicle, and the traveling plan, an evaluation value calculation unit calculating an evaluation value of the traveling plan for each zone, and a map update determination unit determining a necessity of an update of the map information for each zone.