step Fresnel lens of high diffractive efficiency is fabricated by ion beam etching. Diffractive efficiency of Fresnel lens is important factor to evaluate the quality of Fresnel lens. The incident wavelength, except fabrication errors, has effect on diffractive efficiency of Fresnel lens for broadband diffractive refractive hybrid optical system. The effects of incident wavelength on diffractive efficiency of Fresnel lens are analyzed. Four kinds of laser source are used to measure the diffractive efficiency of Fresnel lens. It is pointed that the diffractive efficiency decreases greatly in short wavelength, but one decreases smally in long wavelength.