A travel route searching method of a mobile object whereby a travel route preferred by a user of a mobile object is searched using a road preferred by the user of the mobile object, a travel pattern at a crossroad and a road recommended by other user, and wherein the method comprises the steps of: collecting information of a road traveled by the mobile object, and discriminating a road preference by the collected information of the road to search the travel route; collecting a behavioral factor of the mobile object at a crossroad, and discriminating a behavioral factor preference of the user by the collected behavioral factor to search the travel route; storing as a recommended road the information of the road the mobile object has traveled if there is a instruction of storing the recommended road; and searching a recommended road situated between a starting point and a destination if the travel route is searched. Preference of the user relative to roads, a travel pattern preferred by the user and a recommended route are selectively used for the search of the travel route by the user.