The present invention provides a liquid crystal display device which prevents a decrease in the voltage holding ratio (VHR) of a liquid crystal layer and an increase in ion density (ID) therein and which overcomes problems of defective display such as dropouts, uneven alignment, and screen burn-in. The liquid crystal display device of the present invention prevents a decrease in the voltage holding ratio (VHR) of a liquid crystal layer and an increase in ion density (ID) therein and reduces defective display such as screen burn-in; hence, such a liquid crystal display device is properly used as liquid crystal display devices of a VA mode and PSVA mode which involve active matrix driving and can be applied to liquid crystal display devices of liquid crystal TV sets, monitors, mobile phones, and smartphones.