A method for manufacturing a light transmissive optical component, includes a first etching process of forming a depressed portion by applying etching to a silicon region of a plate-shaped member, a thermal oxidation process of forming a silicon oxide film by thermally oxidizing an inner side surface of the depressed portion, and a nitride film formation process of forming a silicon nitride film that covers the silicon oxide film. Accordingly, it is possible to realize a manufacturing method for an optical component which is capable of uniformly forming a silicon oxide film on a semi-transmissive reflecting surface which is largely inclined (or nearly vertical) with respect to a substrate surface, and an optical component produced by this method.