The present invention provides a curable composition excellent in curability and capable of forming, through light irradiation, a cured product excellent in light resistance, heat resistance, and transparency. The curable composition contains the following component (A), the following component (B), and the following component (C): the component (A): an alicyclic epoxy compound represented by the following formula (a): the component (B): a light resistance imparting agent having a maximum absorption wavelength in a region between 280 and 320 nm in an ultraviolet-visible light absorption spectrum from 250 to 400 nm; and the component (C): an optical cationic polymerization initiator: wherein R1 to R18 are the same as or different from one another and represent a hydrogen atom, a halogen atom, a hydrocarbon group that may contain an oxygen atom or a halogen atom, or an alkoxy group that may have a substituent; and X represents a single bond or a linking group.