A sunroof apparatus includes: a movable panel that can open or close an opening formed in a roof of a vehicle; guide rails having a pair of rail-side holding portions provided side by side in a lateral direction, and respectively provided in both edge portions of the opening in the lateral direction; support brackets, front end portions of which are supported by the guide rails, having vertical walls, and each of which has bracket-side held portions; sliding members are provided so as to be able to move along the guide rails, and each of which has a connection wall; sliding member-side held portions, and sliding member-side holding portions; and an electric driving source driving the movement of the sliding members.