The embodiment of the utility model provides a reverse osmosis seawater desalts system, including a supercharging device, the 2nd supercharging device, reverse osmosis membrane unit, an energy recuperation device, the 2nd energy recuperation device, just permeate membrane unit, turbine power generating equipment, the embodiment of the utility model provides a reverse osmosis seawater desalts system retrieves the pressure energy of strong brine through two -stage energy recuperation device, and strong brine that can the desalination of high -efficient feasible reverse osmosis seawater of utilization generates electricity, can reduce among the discharging process salinity gradient influence to seawater environment.