There are provided an excellent diffractive optical element having a small amount of flare coloring and unaffected optical performance with a decrease in diffraction efficiency minimized and an optical system and an optical apparatus using the diffractive optical element. A diffractive optical element GD used in an optical system OL of a camera 1, which is an optical apparatus, and including a diffraction grating so that the diffractive optical element GD serves as a lens is so configured that the grating height h0 of the diffraction grating in a central region Ac around an optical axis Z is smaller than the grating height hmax of the diffraction grating in a peripheral region Ap.