The invention provides a printed circuit board as well as mother board including printed circuit board adn display device. A display device including: a display panel; a printed circuit board (PCB) including a first substrate and a second substrate; a driving circuit disposed on the first substrate; a carrier connected between the display panel and a pad of the PCB and having a data driving integrated circuit mounted thereon; a protrusion corresponding to the pad and protruding from a side of the second substrate; and a signal line disposed in the protrusion, the first substrate, and the second substrate, the signal line for transmitting a signal from the driving circuit to the carrier.