It is an object of the invention to ensure in a series of contact lenses composed of an assorted plurality of contact lenses having mutually different optical characteristics such as refractive power or the like that each contact lens is capable of exhibiting advantageously and consistently a good wear comfort and tear fluid exchange. In order to attain the object, the present invention arranges each contact lens 10a, 10b, 10c making up the series contact lens designed and having mutually different optical characteristics in the optical zone, such that not only is a shape of the lens back surface 14 of the optical zone 28 identified, but a shape of the peripheral zone 30 is identified at least the outer peripheral zone 44 that contributes to wear comfort and tear fluid exchange.