A selection track setting section in a driving route generation device determines as a selected track a track of a preceding vehicle when a detection section and a track generation section detects a track of the preceding vehicle which is running on the same driving lane of a host vehicle. A candidate track selection section outputs as a candidate track one of tracks of front vehicles, detected by the detection section and the track generation section, other than the track of the preceding vehicle. A switching selection section switches as the selected track from the track of the preceding vehicle to the candidate track when a detection of the track of the preceding vehicle is interrupted during a predetermined detection period. An estimate route generation section generates an estimated driving route of the host vehicle on the bass of the selected track.