An in-the-ear hearing aid comprises a plug (1) for arrangement in the ear channel and having a shell-like wall facing the interior of the ear channel and an exterior faceplate (2) which together define a generally closed cavity (3), in which the individual components of the hearing aid are arranged. An acoustical link in th form of a hose or tube piece (13) is provided between an orifice (14) at the external side of the part of the wall of the plug (1) facing the interior of the ear channel and the residual volume (12) of the internal cavity of the plug (1) and forms together with said residual volume (12) an approximated acoustical circuit having a resonance frequency in the region of the first voice sound formants of the user. Thereby a significantly reduces occlusion effect can be obtained in a simple way in a completed hearing aid.