An optical link is a communications link that consists of a single end-to-end optical circuit. A cable of optical fiber, possibly concatenated into a dark fiber link, is the simplest form of an optical link.

Other forms of optical link can include single-"colour" links over a wavelength division multiplex infrastructure, and/or links that use optical amplifiers to compensate for attenuation over long distances.

Other forms of optical links include free-space optical communication links.