An optical element having compatibility among two or more wavelengths and having an excellent converging performance for light with each wavelength, and an optical head apparatus using the optical element are provided. An optical element according to the present disclosure has a first region including an optical axis and a second region formed around the outer circumference of the first region. The first region and the second region respectively have a first diffraction structure and a second diffraction structure each cyclically formed on an aspheric surface and having a step-like cross section. In the first region, the number of steps included between top portions of the first diffraction structure is different from the number of steps included between the optical axis and a top portion that is closest to the optical axis in the first diffraction structure.