To provide a polarizing element with which display quality is improved by heightening contrast of an optical display device and an optical display device provided with the same.

The polarizing element 20 is provided with a cholesteric layer 21 to selectively reflect either a right-handed circularly polarized light component or a left-handed circularly polarized light component contained in incident light and an absorptive elliptically polarizer 22 stuck in the vicinity of the cholesteric layer 21 to transmit elliptically polarized light containing a circularly polarized light component identical to the circularly polarized light component selectively reflected by the cholesteric layer 21 as the principal component. In this case, an angle (an angle of lamination) between a direction d1 of a major axis of a liquid crystal molecule in the cholesteric layer 21 located on the side of a surface adjacent to the absorptive elliptically polarizer 22 and a direction d2 of a major axis of elliptically polarized light produced by the absorptive elliptically polarizer 22 falls in a specified angle range centering around 90°.