A display device is provided in which a control switching element arranged in a location to which a voltage used for driving a display panel is applied may identify whether an abnormal current has occurred in the display panel in an off-situation so as to easily and accurately detect whether or not a panel defect exists, in a panel defect detection interval wherein the panel defect detection interval is an interval having no abnormal current occurring therein when no panel defect exists. A panel defect detection system and a panel defect detection method are also provided.