Abstract: Device for detecting the operation of a valve, comprising a movable member (15) connected kinematically to a movable part (6) fastened to the closure member of the valve. A detector (24, 25, 26) makes it possible to monitor the displacements or the position of the detection member (15). The detection member (15) has at least one part provided with a predetermined breaking point (20). The kinematic connection between the valve and the detection member (15) can thus be interrupted by the breaking of the member (15) in the event of the jamming of the latter. The invention is in particular applicable to safety valves in nuclear power stations.