A road network analysis system configured to analyze a change in road network based on probe information regarding a vehicular swept path, the road network analysis system comprising: a probe information storing unit configured to store the probe information in time series with respect to a plurality of vehicles; a road network data storing unit configured to store road network data representing a road network; a traffic quantity analysis unit configured to read probe information of a road network in a target area to be analyzed with respect to predetermined time periods before and after a specified reference time from the probe information storing unit and correlate the read probe information to the road network data to calculate a traffic volume with respect to each of existing roads of the road network in each of the predetermined time periods before and after the specified reference time; and a road network change determination unit configured to specify a road having a change in traffic volume of equal to or greater than a predetermined value between the traffic volume in the predetermined time period before the specified reference time and the traffic volume in the predetermined time period after the specified reference time, as a change-related road involved in a change in the road network in a neighborhood of the road; characterised by a route search unit configured to perform route search between two points specified based on the road network data, wherein the road network change determination unit is arranged to specify end points of a plurality of the change-related roads, to control the route search unit to perform route search between end points of different change-related roads and to extract a route overlapped with the change-related road from routes found by the route search. a probe information storing unit configured to store the probe information in time series with respect to a plurality of vehicles; a road network data storing unit configured to store road network data representing a road network; a traffic quantity analysis unit configured to read probe information of a road network in a target area to be analyzed with respect to predetermined time periods before and after a specified reference time from the probe information storing unit and correlate the read probe information to the road network data to calculate a traffic volume with respect to each of existing roads of the road network in each of the predetermined time periods before and after the specified reference time; and a road network change determination unit configured to specify a road having a change in traffic volume of equal to or greater than a predetermined value between the traffic volume in the predetermined time period before the specified reference time and the traffic volume in the predetermined time period after the specified reference time, as a change-related road involved in a change in the road network in a neighborhood of the road; characterised by a route search unit configured to perform route search between two points specified based on the road network data, wherein the road network change determination unit is arranged to specify end points of a plurality of the change-related roads, to control the route search unit to perform route search between end points of different change-related roads and to extract a route overlapped with the change-related road from routes found by the route search.