A device for coupling a coolant supply to a roller, especially for continuous casting installations mounts the roller in a pillow block via journals and roller bearings. The roller can be supplied with a coolant via at least one axial borehole guided through the journals. The device includes a sealing unit, preferably in the form of an elastic sleeve, that can be fixed to the journal in a pressure-tight manner, in order to carry out the coupling to the borehole and a pillow block cover that can be fixed to the pillow block for covering the borehole and includes at least one coolant channel that can be connected to the coolant supply. An insert can be introduced into the pillow block cover in order to couple the borehole to the coolant channel.