[Object] There has been demanded a technique of searching for a travel route that should be targeted, with higher reliability.[Solution] A route search program for finding a guidance travel route to be targeted by a work vehicle causes a computer to achieve a search area setting function of setting, as a search area, a fan shaped area spreading in a travel direction from an own vehicle reference point which is a predetermined reference point of the work vehicle, and a guidance route selection function of selecting, as a guidance travel route to be targeted by the work vehicle, a travel route candidate that is closest to the own vehicle reference point in the search area, from among a plurality of travel route candidates read from a travel route storing unit storing a plurality of travel routes.
