Disclosed is a traffic information generation method for generating traffic information for each link, the method including a vehicle speed detection step of detecting a vehicle speed at predetermined distance intervals or at predetermined time intervals using a vehicle speed sensor; and a traffic jam degree detection step of referring to a specified speed and a specified distance prescribed in association with a traffic jam degree representing a level of a traffic jam and a connection determination distance prescribed in accordance with a road type to detect the traffic jam degree corresponding to the vehicle speed. When a link length falls within a predetermined range, information on the traffic jam degree corresponding to a fastest vehicle speed within a prescribed starting point distance from a beginning of the link is allocated to the link.