Provided are a display panel and a three-dimensional (3D) display device and a 3D head-up display (HUD) device using the display panel. The display panel includes a plurality of pixels, and a plurality of placement spaces provided between the plurality of pixels, wherein the plurality of pixels are uniformly provided in the display panel based on a pattern corresponding to the plurality of placement spaces, and wherein a frequency corresponding to a repetition interval of the pattern is outside of a cognitive frequency band that is visible to a user.