A map information processing apparatus includes a road matching means (143) for comparing the road data with current position data to carry out map matching, an input unit (130) for inputting both a specified detection start point and a specified detection end point, an unregistered road detection means (144) to which both the specified detection start point and the specified detection end point are inputted, for detecting, as an unregistered road, a section between a detection start point and a detection end point of the unregistered road which are acquired on the basis of either the map matching carried out by the road matching means or the result of comparison between running track data and the road data, and a road data generating means (145) for generating road data corresponding to the detected unregistered road and storing the road data in a map data storage means.