A coupling device for the detachable coupling of a front loader (1) to an agricultural tractor (20) using a coupling bracket (4) which is connected to the loader (1) and a coupling bracket (3) which is connected to the tractor (20). The two brackets are coupled to one another by co-operating coupling element means (5b,5c:3a,3c). A locking element (6), which is mounted on the leader coupling bracket (4), can be pre-tensioned into a locked position and, by actuating an actuation element (7), can be moved into an unlocked position. A securing element (8) is provided, which is pre-tensioned into a securing position and to which the locking element (6) is coupled in such a way that, when an external force is applied to the locking element to move it towards the unlocked position, it contacts the tractor coupling bracket (3d) to prevent a further movement of the locking element towards the unlocked position. The actuation element (7) is coupled in such a way to the locking element (6) and the securing element (8) that, when an actuation of the actuation element (7) takes place, the securing element (8) is moved out of the securing position and, subsequently or simultaneously, the locking element (6) is moved together with the securing element (8) into the unlocked position.
