A server device includes a storage unit configured to store vehicle information including vehicle behavior information and position information, a region specifying unit configured to specify a warning road region where a sudden stop of a vehicle occurs a plurality of times based on the stored vehicle information, and a notification unit configured to, when the sudden stop of the vehicle occurs in the specified warning road region, notify terminal devices that correspond to vehicles located in the warning road region and in a vicinity of the warning road region of information regarding the warning road region.