The present invention relates to a membrane-based desalination method capable of recovering osmotic energy. In detail, with a membrane-based desalination process using osmotic energy through pressure recovery according to an aspect of the present invention, there can be provided a membrane-based desalination method capable of recovering osmotic energy that comprises the steps of: A gathering a first solution from raw water containing sa B raising the pressure of the first solution in a pressure exchange device; C separating the first solution into a second solution and a third solution; D pressurizing the second solution; E raising the pressure of the third solution in a second pressure exchange device; F mixing the second solution and the third solution with a fourth solution and supplying the fourth solution to a first semi-permeable membrane to obtain generation water; G transferring a fifth solution that remains after obtaining the generation water from the fourth solution, to the second pressure exchange device, to transfer pressure to the third solution, and then transferring the fifth solution to the semi-permeable membrane; H obtaining a sixth solution having a salinity lower than that of the fifth solution from the raw water; I supplying the sixth solution to the semi-permeable membrane so that water is transferred between the sixth solution and the fifth solution by means of a difference in salinity to decrease the salinity of the fifth solution and increase the volume of the fifth solution, wherein the fifth solution via the I step flows into the first pressure exchange device to supply pressure the first solution and then raise the pressure of the first solution in the B step.
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