A branch point diagram system includes a terminal disposed on a movable body for displaying a branch point diagram of a branch point and a delivery server for delivering branch road part to the terminal according to a delivery schedule when the terminal approaches a branch point. The delivery server calculates the delivery load of delivering the branch road part according to the schedule. In view of the calculation results of the delivery load, the delivery schedule is revised, and the branch road part is delivered to the terminal according to the revised schedule. The terminal then displays the branch point diagram for the branch point after generating the branch point diagram based on the branch road parts and positional data received from the delivery.