ROAD SURVEILLANCE SYSTEM, ROAD SURVEILLANCE METHOD, AND NON-TRANSITORY STORAGE MEDIUM

To improve efficiency of road surveillance, a road surveillance system includes a detection unit 122 and a processing unit 134. The detection unit 122 detects a road state being a state of an object on a road by processing an image in which the road is captured. The processing unit 134 performs, when the road state satisfies a first criterion, any of notification processing of making a notification of the road state that satisfies the first criterion according to notification setting related to the notification, and change-related processing related to a change in the notification setting, based on whether a second criterion is satisfied. The second criterion is a criterion related to a determination result of whether the road state satisfies the first criterion.