A locking device for locking a transported on a transport vehicle cutter for a harvesting machine with respect to a supporting frame of the transport vehicle comprises a, for example, cutting side clutch section (11), and an example vehicle-side receiver (35) for the coupling portion which can be brought together into locking engagement. The coupling portion includes a base (15), a portion extending from the base shaft (17) and a relative to the shaft projecting head (19). The receptacle has a stop surface for the base of the coupling portion and an opening for the passage of at least the head of the coupling portion in a feed-through direction. At the receiving a locking element (60) is provided which is movable between a release position and a locking position and is adapted to engage behind the guided through the opening head (19) of the coupling portion in the locking position.
