Abstract: A detecting element has an absorbing section where a temperature rises according to an amount of electromagnetic waves which are absorbed and a detecting section where characteristics change according to an amount of heat which is transmitted from the absorbing section. A method for manufacturing the detecting element includes: forming the detecting section on a substrate; forming a protective film which covers the detecting section; forming a hollow space portion in a region which overlaps with the detecting section of the substrate in a planar view after the forming of the protective film; and forming the absorbing section by applying a liquid body, which contains a material constituting the absorbing section, in a region on the protective film on an opposite side from the detection section, which overlaps with the detecting section in a planar view, and solidifying the liquid body after the forming of the hollow space portion.