A connection device including a tubular male termination, a connecting means adapted to be mounted around and accommodated in a groove of the female termination, and a locking member for locking these means in the female termination to be mounted around the male termination to reversibly move these means into a locking position in the groove. The device includes means for immobilizing and releasing the locking member that are rigidly fastened to the male termination, these means being adapted to prevent the connecting means from being moved to the locking position unless the male termination occupies a predetermined insertion position in the female termination and, only if the male termination has reached that position, to release the locking member, while allowing its movement toward the female termination so that a thrust on this member moves the connecting means into the locking position.