A sealing device seals a pressure or vacuum zone of a roller having a roller sleeve which is movable in relation to the sealing device. The sealing device has a sealing strip with an upper side forming a sealing face and a lubricant channel adjoining the sealing face and is formed by at least one groove-type depression in the sealing strip, which extends in the longitudinal direction of the sealing strip. When the sealing device is installed, the sealing face and the opening of the groove-type depression face toward the inner side of the roller sleeve. The lubricant channel is hooked up to a supply line which at least in portions runs within the sealing strip and delivers lubricant between the inner side of the roller sleeve and the sealing face. The sealing strip, at each of its two ends, has a wall delimiting the lubricant channel in its length.