Abstract: Device for cleaning of surfaces under water, such as ship hulls, includes a rotary disc furnished with nozzles for discharge of pressurized liquid against the surface to be cleaned. The nozzles are mounted obliquely in relation to the rotational axis of the rotary disc and are arranged to be supplied with pressurized liquid through a hollow spindle that is concentric with the rotational axis. The nozzles have an inclination that have an orientation involving that the velocity component (Vp) of the liquid jet from each nozzle that is not perpendicular to the surface to be cleaned, has a tangential velocity component (Vt) that has the same direction as the direction of rotation (R) of the rotary disc and optionally a radial velocity component that is positive, i.e. that is directed outwards in relation to the center of the disc.