In a hydraulic camshaft adjuster for an internal combustion engine including a hydraulic operating unit for adjusting the angular position of the camshaft relative to a camshaft drive by way of a hydraulic control valve with a valve housing in which a control piston is disposed for controlling the supply of hydraulic fluid to, and its removal from, the hydraulic operating unit and to which hydraulic fluid is supplied from the camshaft by way of a pressure channel which is formed into the valve housing so as to extend along the outer surface thereof and a sleeve tightly surrounds at least the part of the valve housing which includes the channel for tightly covering the channel.