A distance measurement apparatus includes: an imaging device which captures an image; a diffractive optical device which diffracts a subject image; an optical system which forms, on the imaging device, the image from the subject image diffracted by the diffractive optical device; and a distance measurement unit which measures a distance to a subject using the image captured by the imaging device. The distance measurement unit measures the distance to the subject based on an interval between diffraction figures of the subject image which are created by the diffractive optical device. The interval is on the image captured by the imaging device.