A display device includes a display pad disposed on a substrate and including at least one through hole penetrating in a thickness direction of the substrate, at least one first protrusion pattern filling the at least one through hole and protruding above the display pad, a pad connection pattern overlapping the at least one first protrusion pattern and electrically connected to the display pad, and a connection lead of a circuit board, the connection lead being disposed on the pad connection pattern and electrically connected to the pad connection pattern.