Self-closing valve device, preferably self-closing sanitary mixing and shut-off valve device, comprising - a valve closing body unit which, in a normal operation mode of the self-closing valve device, is disposed to be movable between a valve closed position and a normal operation valve open position, - a valve actuation unit which, in a stationary closed position, retains the valve closing body unit in the valve closed position thereof and, in a temporary open position, retains the valve closing body unit in the normal operation valve open position, wherein the valve actuation unit from its stationary closed position reaches its temporary open position upon user-operation and from its temporary open position reaches its stationary closed position in a self-acting manner, and - a user-operated adjustment unit which is configured for adjusting the valve actuation unit in a special operation mode of the self-closing valve device from its stationary closed position to a stationary special operation position in which the valve actuation unit retains the valve closing body unit in a special operation valve open position, - wherein the valve actuation unit comprises an actuation member which is disposed to be movable between a first open state, that it takes when the valve actuation unit is in its temporary open position, and a coupling closed state, that it takes when the valve actuation unit is in its stationary closed position, wherein the adjustment unit, when in the special operation mode of the self-closing valve device it adjusts the valve actuation unit to the stationary special operation position thereof, adjusts the actuation member from the coupling closed state to a second open state, characterized in that - the valve actuation unit comprises a hydraulic damper unit which comprises a user-operated axially movable hydraulic cylinder having a piston chamber, a displacement piston disposed in the piston chamber to be movable between a stationary piston end state and a transient piston end state, to which displacement piston the actuation member is movement-coupled and which displacement piston subdivides the piston chamber in two half chambers (16a, 16b), a hydraulic fluid passage connection between the two half chambers which opens upon movement of the displacement piston in the direction towards its transient piston end state and closes upon movement of the displacement piston in the direction towards its stationary piston end state, and a hydraulic fluid restrictor connection between the two half chambers which is open at least upon movement of the displacement piston in the direction towards its stationary piston end state. - a valve closing body unit which, in a normal operation mode of the self-closing valve device, is disposed to be movable between a valve closed position and a normal operation valve open position, - a valve actuation unit which, in a stationary closed position, retains the valve closing body unit in the valve closed position thereof and, in a temporary open position, retains the valve closing body unit in the normal operation valve open position, wherein the valve actuation unit from its stationary closed position reaches its temporary open position upon user-operation and from its temporary open position reaches its stationary closed position in a self-acting manner, and - a user-operated adjustment unit which is configured for adjusting the valve actuation unit in a special operation mode of the self-closing valve device from its stationary closed position to a stationary special operation position in which the valve actuation unit retains the valve closing body unit in a special operation valve open position, - wherein the valve actuation unit comprises an actuation member which is disposed to be movable between a first open state, that it takes when the valve actuation unit is in its temporary open position, and a coupling closed state, that it takes when the valve actuation unit is in its stationary closed position, wherein the adjustment unit, when in the special operation mode of the self-closing valve device it adjusts the valve actuation unit to the stationary special operation position thereof, adjusts the actuation member from the coupling closed state to a second open state, characterized in that - the valve actuation unit comprises a hydraulic damper unit which comprises a user-operated axially movable hydraulic cylinder having a piston chamber, a displacement piston disposed in the piston chamber to be movable between a stationary piston end state and a transient piston end state, to which displacement piston the actuation member is movement-coupled and which displacement piston subdivides the piston chamber in two half chambers (16a, 16b), a hydraulic fluid passage connection between the two half chambers which opens upon movement of the displacement piston in the direction towards its transient piston end state and closes upon movement of the displacement piston in the direction towards its stationary piston end state, and a hydraulic fluid restrictor connection between the two half chambers which is open at least upon movement of the displacement piston in the direction towards its stationary piston end state.