Provided is a transportation device for loading a cargo and moving in a moving direction, comprising: a bed for loading a cargo thereon; four leg parts for being able to receive a part of a weight of the bed individually; a movable part for moving the leg parts individually to change relative positions with respect to the bed individually; and a control part for controlling the movable part for the four leg parts individually, wherein the control part is for changing the relative position of at least one of the four leg parts with respect to the bed within a range in which a center of gravity of the bed is located inside a profile of a horizontal triangle made by three leg parts among the four leg parts as apexes, causing the three leg parts to support the bed and releasing one remaining leg part from supporting the bed.