A disconnectable mooring system for a vessel is presented, comprising a moonpool in the vessel, a turret structure mounted for a rotation in said moonpool and a buoy member having a plurality of passages each adapted to receive a riser. The turret structure has a lower end comprising a buoy receptacle for detachably receiving the buoy member, wherein the mooring system further comprises a plurality of mooring lines for transmitting mooring forces and each have a lower end and an upper end connected to the seabed and the buoy member, respectively. The mooring lines each comprise a first section which in a disconnectable manner is connected to the turret structure and a second section connected to the first section at a coupling point and connected to the buoy member. Also methods for disconnecting and reconnecting such a mooring system are presented.