A first head unit configured to discharge a liquid, a unit holder detachably holding the first unit, and a member configured to move relative to the unit holder are provided. When a trajectory through which the first head unit passes when the first head unit is attached and detached with the unit holder is used as the first trajectory, the member is configured to move between a first position at which the member is positioned relative to the unit holder so as to overlap the first trajectory, and a second position at which the member is positioned relative to the unit holder separated from the first trajectory.