A parallax barrier type stereoscopic image display device comprises: an image panel that display a left-eye image and a right-eye image; a barrier panel that has a switchable barrier comprising a liquid crystal layer, a reference electrode positioned above the liquid crystal layer, and a plurality of driving electrode channels positioned below the liquid crystal layer, each of which is controlled independently, and selectively blocks light from the image panel; and a driver that supplies a reference voltage to the reference electrode and applies a channel driving voltage to the driving electrode channels to form a barrier area and an open area in the switchable barrier.