The invention discloses a marine fresh-water production and supply system and device directly driven by utilizing marine renewable energy. The marine fresh-water production and supply system comprises a headquarter base and a plurality of marine fresh-water production platforms arranged along a sea route, wherein the headquarter base comprises a monitoring center and an operation center which communicate in a wireless manner; the marine fresh-water production platforms communicate with the monitoring center in a wireless manner; the marine fresh-water production platform can meet the requirement of fresh water for ships with longer route, the ships does not need to store more fresh water in the navigation process, so that the consumption of fuel can be saved; and a marine floating platform adopts a mooring technology combining anchors and weights, can adapt to sea conditions in a larger range and is not limited by the depth and the severe weather of the ocean. The marine fresh-water production and supply system and device disclosed by the invention have the advantages that a reverse-osmosis seawater desalination system can be directly driven to produce fresh water by utilizing the wind energy and the wave energy on the sea, the needed devices are fewer, the energy efficiency is high, and the comprehensive cost is low; and the marine fresh-water production and supply system and device can lay foundation for building maritime silk roads, and also can produce and supply the fresh water for open-sea fishery operation ships and open-sea seabed resource development platforms.