The method of making an optical lens in accordance with the present invention comprises an optical lens preform producing step of producing an optical lens preform 40 having a plurality of curved surface parts 43 formed parallel to each other, and a pair of flanges 48 formed on both sides of the plurality of curved surface parts 43; a drawing step of drawing the optical lens preform 40; and an optical lens producing step of producing an optical lens 1 by cutting the drawn optical lens preform 40; wherein the plurality of curved surface parts 43 of the optical lens preform 40 drawn by the drawing step function as an optically effective part. In such a method, the form of the optically effective part can be determined in the stage of the preform before drawing, whereby the optically effective part can be processed in a sufficiently large size.