A color display device includes a color cathode ray tube having a phosphor screen, a color selection electrode and an electron gun for projecting plural in-line electron beams toward the phosphor screen, a deflection device for deflecting the electron beams horizontally and vertically, an electron beam correction apparatus including a correction coil wound around the tube axis, a deflection circuit for driving the deflection device, and an electron beam correction circuit for supplying to the electron beam correction apparatus a generally rectangular-wave signal having a period equal to two times a period of the vertical deflection of the electron beams and in synchronism with the vertical deflection of the electron beams.