A route guidance unit includes: a detection unit (10, 20) configured to detect a position of a host vehicle; a guide unit (64) configured to provide guidance on a travel route when a distance from the position of the host vehicle detected by the detection unit (10, 20) to a branch point on the travel route reaches a predetermined distance; and an accuracy determination unit (63) configured to determine a degree of accuracy of the position of the host vehicle, wherein, when the accuracy determination unit (63) determines that the degree of accuracy of the position is a predetermined threshold or less, the guide unit (64) provides the guidance on the travel route at a point before the distance from the position of the host vehicle to the branch point reaches the predetermined distance.