A display device includes: a display panel including first pads arranged along a first direction, and second pads spaced apart from the first pads; a first connection circuit board electrically connected to the first pads; and a second connection circuit board electrically connected to the second pads. The first connection circuit board includes: first output pads electrically connected to the first pads; and at least two first protrusion parts spaced along the first direction and protruding in a second direction crossing the first direction. The second connection circuit board includes: second output pads electrically connected to the second pads; and at least one second protrusion part protruding in the second direction, and located between the first protrusion parts when viewed on a plane that is parallel to a surface of the display panel.