A combined riser, offloading and mooring system is provided for the offloading of hydrocarbons from a floating production vessel (FPV), onto a tanker. The system preferably includes an offloading buoy tethered to the mudline by at least one mooring line. The offloading buoy and the mooring line can be part of an offloading buoy system for supporting a production riser and fluid jumper lines. Additionally, the offloading buoy system can support an offloading jumper line from the FPV to a fluid connector on the offloading buoy system through which hydrocarbon fluid is loaded via an offloading hose onto a tanker. The combined riser, offloading and mooring system also preferably includes at least one set of FPV mooring lines for securing the floating production vessel to the offloading buoy system. The system further preferably includes a hawser line for connecting the tanker to the offloading buoy system. In this manner, the number of mooring lines for the floating production vessel may be reduced.