A mobile object according to the invention includes: a moving base including a front base and a rear base； a seat including a seating part and a leg part configured so as to support the seating part； and a frame disposed on the rear base, in which the leg part includes: the seating part attaching region to be attached to the seating part, the base attaching region to be attached to the front base so as to be pivotable, and a frame attaching region to be attached to the frame so as to be pivotable, the front and rear bases are movable relative to each other such that the moving base can change between the expanded state and the contracted state of the wheelbase, the pivotal movement of the leg part is interlocked with the relative movement between the front and rear bases, the frame is configured so as to cover the seating part attaching region and the frame attaching region from an outside of the mobile object in the width direction when the moving base is in the expanded state, and cover the base attaching region and the frame attaching region of the leg part from an outside of the mobile object in the width direction when the moving base is in the contracted state.
