A color picture tube satisfies the following conditions. First, a value of df(r)/dr is zero in a first area on an inner surface of a panel which includes a point at which r=0, and is negative in a second area from an outside of the first area to the point at which r=L.sub.d, where r denotes a radial distance from the Z-axis, and f(r) denotes a position of a point on the inner surface of the panel in a direction of the Z-axis, and the point at which r=L.sub.d denotes an outermost point in a diagonal direction of the image display area. Second, a value of d.sup.2 f(r)/dr.sup.2 is negative in a third area from the point at which r=0 to an inside of a point at which r=R.sub.2 being within the second area, is zero at the point at which r=R.sub.2, and is positive in a fourth area from an outside of the point at which r=R.sub.2 to the point at which r=L.sub.d. Third, a thickness of the panel in the second area in the direction of the Z-axis is larger than that in the first area in the direction of the Z-axis.