1. A 3D image display device, comprising: a display device including a plurality of pixels and displaying each of a left-eye image and a right-eye image, wherein the display device inserts an insertion image between the left-eye image and the right-eye image such that the left-eye image is displayed for part of four frames and the insertion image is displayed for the remaining frames and the right-eye image is displayed for part of four other frames and the insertion image is displayed for the remaining other frames.