A display device includes; a touch panel device including; a touch panel and a touch controller connected to the touch panel, the touch controller including; a sampling unit which samples a sensing output signal input thereto from the touch panel to generate a sampled signal, and an analog/digital converter which converts the sampled signal to generate contact information, and a display panel device including; a display panel, a gate driver which applies a gate signal to the display panel, and a data driver which applies a data voltage to the display panel, wherein the sampling unit samples a portion of the sensing output signal which does not include a coupling noise.