A 3D display device and LC barrier are disclosed. The 3D display device comprises a non-polarized light display unit and an LC barrier. The LC barrier comprises a liquid crystal cell arranged at one side of the non-polarized light display unit, and the liquid crystal cell comprises an upper substrate, a lower substrate and a cholesteric liquid crystal layer between the substrates; a first quarter-wave plate provided on the upper substrate; a polarizer provided on the first quarter-wave plate; an absorption axis of the polarizer forms a predetermined angle with a fast axis of the first quarter-wave plate.