Disclosed herein is a coupling device for a tube comprising a sleeve part for receiving a part of the tube, and a sealing organ which is arranged to provide a seal around the tube as it is at least partially inserted into the sleeve part, wherein the sealing organ comprises a rubber ring of which at least a first portion is placed between the tube and the elements and a second portion is placed between the elements and the sleeve part, wherein the elements are provided with circumferentially extending cooperating tongue and groove connections, which are positioned at the sides of the elements facing the second portion of the rubber ring that lies adjacent to the sleeve part.