A display device includes a display panel including panel pads adjacent to the side surface of a display panel; connection pads disposed on the side surface of the display panel and connected to the panel pads; and a circuit board disposed on the side surface of the display panel and including lead signal lines directly bonded to the connection pads, wherein the connection pads include a first connection pad, a second connection pad disposed on the first connection pad, and a third connection pad disposed on the second connection pad, and the first connection pad is in contact with corresponding one of the panel pads, and the third connection pad is directly bonded to corresponding one of the lead signal lines.