Provided is a seawater desalination system including reverse osmosis membrane modules each including: a reverse osmosis membrane; and a pressure vessel installing the reverse osmosis membrane, and configured to obtain permeated water and concentrated water using the reverse osmosis membranes housed in the reverse osmosis membrane modules by supplying seawater to the reverse osmosis membrane modules. The seawater desalination system includes a module group including the reverse osmosis membrane modules connected together in parallel. The seawater is supplied to each of the reverse osmosis membrane modules by being supplied to the module group through first and second seawater supply routes. The first and second seawater supply routes are each provided with a liquid transport pump configured to supply the seawater flowing through the seawater supply route to the module group.