A retardation plate is provided and includes: a transparent support; and an optically anisotropic layer formed from a discotic liquid crystalline compound. The discotic liquid crystalline compound has a molecule oriented and fixed with an angle between a discotic plane of the molecule and a plane of the transparent plane substantially being a right angle, and the discotic liquid crystalline compound has a wavelength dispersion value smaller than that of compound (A): ##STR00001##