Abstract: A disconnectable mooring system for a vessel comprises a mooring buoy member and a turret structure mounted in a moonpool of the vessel. The mooring buoy member is anchored to the seabed and has a plurality of passages each adapted to receive a riser. The turret structure has a receptacle for receiving the buoy member and locking means for locking the buoy member in the receptacle. The turret structure accommodates a plurality of conduits to be connected to risers installed in passages of the buoy member and the turret structure is rotatably supported in the moonpool of the vessel by means of at least a bearing assembly mounted above sea level. The buoy member is provided with a conical outer casing and the receptacle of the turret structure has a cone shape corresponding to the conical outer casing of the buoy member. The turret structure comprises a turntable carrying the conduits to be connected to the risers.