To provide an optical system component that decreases reflectance of off-axis light made incident inside and that, as a result, suppresses generation of what we call flare, ghost, etc., and improves image quality.

In the optical system component 1 for housing optical elements 2, 3 inside, the inner wall face 10 of the component is coated with a black coating film 15 formed from a film forming resin 16 containing a plurality of fine particles 17, wherein the plurality of fine particles have shapes of a plurality of types.