A display device includes a display panel including a plurality of pixels, a first panel pad, and a second panel pad and a circuit board including a first substrate pad and a second substrate pad to apply a first power voltage to the first panel pad and the second panel. The display panel further includes a first power line pattern connected to the second substrate pad to apply the first power voltage to the pixels and a second power line pattern connected to the first substrate pad. The circuit board includes a first electrostatic discharge protection circuit connected between the first substrate pad and the second substrate pad, a substrate power pattern electrically connected to the first substrate pad, a ground pattern receiving a ground voltage, and a second electrostatic discharge protection circuit connected between the substrate power pattern and the ground pattern.