<p>Provided is an objective lens element having superior interchangeability between optical disks having different substrate thicknesses. The objective lens element (141) gathers a first incident light flux having a wavelength (?1) through a substrate having a substrate thickness (t1), and gathers a second incident light flux having a wavelength (?2) which is longer than the wavelength (?1) through a substrate having a substrate thickness (t2) which is larger than the substrate thickness (t1). One side of an optical function surface is divided into an inner circumferential portion (131B) including an axis of rotational symmetry, and an outer circumferential portion (131F) which is a ring band shaped region surrounding the inner circumferential portion (131B). The inner circumferential portion (131B) is provided with a plurality of discontinuous steps. The plurality of steps have different heights varying in one direction from the light axis toward the outer circumferential portion, and each of the steps generates a constant optical path difference longer than the wavelength (?1) with respect to the first incident light flux (61), and generates a constant optical path difference shorter than the wavelength (?2) with respect to the second incident light flux (62).</p>
