An apparatus for inspecting an edge portion of a substrate can inspect a defect or a chamfered width on an edge portion of a substrate. First and second right-angled prisms are disposed above and below the edge portion such that inclined surfaces thereof are directed toward the upper surface and lower surface of the edge portion. A lighting part irradiates the edge portion of the substrate with light. A photographing part is disposed adjacent to the edge portion. The photographing part takes an image of the upper surface of the edge portion from light that has passed through the first right-angled prism, an image of the lower surface of the edge portion from light that has passed through the second right-angled prism, and an image of an end surface of the edge portion.