A method for the desalination of water, carried out in one embodiment on the basis of a borehole (4) in permeable coastal land, in which two internal wells (5, 6) are interconnected at the bottom, by means of a membrane packet (9), disposed such that the supply flow provided via the borehole (4) flows in a downward direction by the suction of a motor pump (7) installed at a shallow depth inside the well (5), with an ascending flow, pouring same to the marine outlet and the diluted flow (permeate) drains from the membrane packets (9) to the second well (6), which is hollow and at atmospheric pressure, where a motor pump (8) extracts the permeate for the use thereof, while in another embodiment the membrane packets (15) may be disposed in ducts hanging from a floating platform anchored in the sea or other salty water.