Abstract: A hydraulic control device for an emergency stop valve of a steam turbine has a module for reducing a hydraulic pressure by rapid opening of an outflow valve and/or unloading or loading an actuator for actuating the emergency stop valve. In an operating medium supply and/or conducting system a control valve arrangement with at least three safety valves is provided, which are hydraulically interconnected such that they open the outflow valve or unload or load the actuator only when a safety circuit by way of at least two safety valves of the control valve arrangement has assumed an emergency stop position. A precontrol valve that is independent from the remaining safety valves is hydraulically connected upstream of each safety valve. A safety valve that is connected downstream of a respective precontrol valve can be hydraulically decoupled from the same during the operation.