NOVELTY - A sea water desalination system comprises a membrane bioreactor (1) which permeates sewage, and removes and purifies activated sludge, reverse osmosis film (2) which generates industrial water while transmitting permeated water through membrane bioreactor, an ultra-filtration membrane which permeates the seawater and removes particles in the seawater, reverse osmosis film (4) which generates drinking water while the treated water which transmitted the ultra-filtration membrane is permeated, a stirring apparatus, and reverse osmosis film (6).    USE - Sea water desalination system for preparing industrial water and drinking water from seawater and sewage.    ADVANTAGE - The sea water desalination system is economical.    DETAILED DESCRIPTION - A sea water desalination system comprises a membrane bioreactor which permeates sewage, and removes and purifies activated sludge, reverse osmosis film (2) which generates industrial water while transmitting permeated water through membrane bioreactor, an ultra-filtration membrane (3) which permeates the seawater and removes particles in the seawater, reverse osmosis film (4) which generates drinking water while the treated water which transmitted the ultra-filtration membrane is permeated, a stirring apparatus (5), and reverse osmosis film (6) which generates industrial water while the liquid mixture stirred by the stirring apparatus is permeated. The salt content contained in tertiary concentrated water is removed. The salt content contained in secondary concentrated water is removed. The secondary concentrated water removed with reverse osmosis film (4) and primary concentrated water removed with reverse osmosis film (2) are sent and stirred in the stirring apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic structure of sea water desalination system. (Drawing includes non-English language text)    Membrane bioreactor (1)    Reverse osmosis films (2,4,6)    Ultra-filtration membrane (3)    Stirring apparatus (5)    Motive power collection apparatus (34)