An imaging lens is provided and includes: in order from an object side of the imaging lens, a first lens having a positive refractive power; an aperture stop; a second lens having one of a positive refractive power and a negative refractive power; and a third lens that corrects for aberration. At least one of the first and second lenses has a diffractive optical surface, the diffractive optical surface having twenty or less orbicular gratings in a range to pass an effective light ray. An imaging lens is obtained, which is short in overall length and capable of obtaining optical performances favorably even when the imaging lens is made in the three-lens structure. |