A circularly polarizing plate has a polarizer and two λ/4 plates (T1, T2) bonded respectively onto both sides of the polarizer so as to face each other, the circularly polarizing plate is characterized in that the in-plane retardation values Ro of the λ/4 plates (T1) and the λ/4 plates (T2) satisfy (a) to (c) below in an environment with a temperature of 23° C. and RH of 55%. (a) The in-plane retardation value Ro of the λ/4 plates (T1), when measured within the range of 450 to 650 nm, is 3.0 to 20.0 nm smaller than the in-plane retardation value Ro of the λ/4 plates (T2). (b) The in-plane retardation value Ro of the λ/4 plates (T1) (450) falls within the range of 110 to 140 nm. (c) The in-plane retardation value Ro of the λ/4 plates (T2) (650) falls within the range of 145 to 165 nm.