In a crawler vehicle, at the time of crane operation at a place where a grounding space of crawlers is limited, a land leveling preparation is suppressed as little as possible so as to improve efficiency of the operation. The crawler vehicle is provided with left and right crawler frames on the both left and right sides of a track frame. The crawler frames can be moved between an expansion position for maximizing a distance between centers of the crawlers and a contraction position for minimizing the distance. Further, the crawler vehicle can position the crawler frames to the track frame at an intermediate position in the middle of the expansion position and the contraction position.