To provide a method and an apparatus for optical inspection of metals, etc., which quickly and reliably discriminates fine flaws, etc., appearing on the surface of a metal, etc., during working thereof and inspects the surface at a high precision.

The optical surface inspection method of inspecting the irregularities condition of the surface of a rolled or drawn metal, etc., uses an illuminator for radiating a light having a fringe pattern of bright zones and dark zones alternately arranged with equal spacings on the surface of a metal, etc., under inspection, and sets so that the arranging direction of the fringe pattern is equal to the rolling or drawing direction.