Abstract: Disclosed are a display device and a driving method thereof, which when a frame having a long time length and a frame having a short time length are alternately provided, prevent a DC voltage stress from being accumulated. One frame of a plurality of frames may be driven in the line inversion method, and a polarity may be delayed up to a next frame, thereby allowing polarities to be alternately supplied. Therefore, a time length of the positive voltage may be the same as that of the negative voltage, and thus, the positive voltage and the negative voltage may be continuously supplied based on a frequency of another frame, thereby solving a problem where the DC voltage stress is accumulated due to a difference between the time length of the positive voltage and the time length of the negative voltage.