A polarization control unit which prevents moire and a 2D and 3D image display device having the same are provided. The polarization control unit in one example includes first and second substrates positioned opposite to each other, a first electrode disposed on a surface of the first substrate, a second electrode disposed on a surface of the second substrate, and a polymer-dispersed liquid crystal layer disposed between the first and second electrodes. The polymer-dispersed liquid crystal layer can include partition walls supporting the first and second substrates, and liquid crystal molecules arranged in a space defined by the partition walls. The partition walls can be arranged to form a inclination angle with the vertical plane.