A control valve for a device to variably adjust control times of gas-exchange valves of an internal combustion engine. The control device has a valve housing and a control piston. The valve housing has an axial cavity with a dividing element arranged in the cavity that separates the cavity into two partial spaces and hydraulically seals the spaces from one another. The dividing element is produced separately from the valve housing and is positionally fixedly fastened in the cavity of the valve housing. The first partial space holds the control piston, and a supply connection is formed in the region of the first partial space. The second partial space has at least one first opening via which pressure medium can be supplied to the second partial space by a pressure medium pump, and at least one second opening by which the second partial space communicates with the supply connection.