A display device includes a display panel including a plurality of pixels, a gate driving circuit outputting a plurality of gate signals to the pixels, and a detection circuit receiving a first gate signal and a second gate signal among the gate signals, comparing a first voltage difference between a first high voltage of the first gate signal and a reference voltage with a second voltage difference between a second high voltage of the second gate signal and the reference voltage to obtained a compared result, and determining whether the first and second gate signals are normal signals based on the compared result.