Abstract: The invention is directed to a coupling assembly having a male member (1) with a spigot (5) to be received in an opening (21) in a female member (2), and a radially deformable retaining element (3) which is arranged in a recess (22) in the female member (2) and is radially elastically deformable and adapted to be urged into the recess (22) during the coupling operation by a support element (12) disposed on the spigot (5). In the locked position, the spigot (5) is locked against being pulled out of the opening due to the cooperation between the support element (12) and the retaining element (3). To uncouple the coupling assembly, an unlocking element (15) is provided. The support element (15) is releasably connected with the spigot (5) in order to enable assembly of the unlocking element (15).