Abstract: The disclosure relates to a magneto-optical reading head. A magneto-optical head comprises an optically active part which is a very thin magnetic layer that causes the rotation of the plane of polarization of the light as a function of its magnetic polarization which is itself linked to the magnetic polarization of the magnetic tape that bears the information elements to be read and moves past the thin layer. Instead of using a focusing optical device to illuminate the optically active part, it is provided that the head will comprise an optical guide which ends directly before the active part and is such that the plane of incidence of the light rays on the optically active part is perpendicular to the general direction of elongation of a gap region before which the magnetic tape passes.