A wire guide body includes: a vehicle body-side guide portion having a configuration in which a plurality of vehicle body-side link members are coupled so as to form a string and to be capable of being curved as seen in a plan view, the vehicle body-side guide portion being coupled to a vehicle body-side bracket; a door-side guide portion having a configuration in which a plurality of door-side link members are coupled so as to form a string and to be capable of being curved as seen in a plan view, the door-side guide portion being coupled to a door-side bracket; and a relay link member including a vehicle body-side coupling portion that is coupled to the vehicle body-side guide portion, and a door-side coupling portion that is disposed at a position lower than the vehicle body-side coupling portion and that is coupled to the door-side guide portion.