A device for cooling and lubricating a subsea device (1) which includes an electric rotary machine (4) and a fluid-rotation machine (6-8) drive-connected (5) thereto, which electric rotary machine (4) has a lubrication/cooling circuit includes a cooler (11) exposed towards the surrounding seawater, and where the fluid-rotation machine (6-8) has a fluid pressure at the end facing towards the electric rotary machine (4). The lubrication/cooling circuit (12, 11, 14) is pressure-impacted by the fluid pressure at one point (19, 20) in the lubrication/cooling circuit outside the fluid-rotation machine (6-8).