There is provided a method for inspecting a substrate including: irradiating an illumination light onto a first surface or a second surface opposite to the first surface, of a substrate in which a pattern having a periodicity and extending from the first surface to an inside of the substrate is formed in the first surface, the illumination light having a permeability to permeate the substrate to a predetermined depth; detecting a light reflected from or transmitted through the substrate due to irradiation of the illumination light; and inspecting the substrate by utilizing information based on the periodicity of the pattern obtained from detection of the light reflected from or transmitted through the substrate.