This system for concentrating solvent-containing articles involves a first step in which: a supply flow (a) comprising solvent-containing articles containing a solute and a solvent (b) is caused to flow counter to or parallel with a permeant flow (d) through a forward osmosis membrane (o); the solvent (b) contained in the supply flow (a) is made to pass through the forward osmosis membrane (o) and to move into the permeant flow (d); and a concentrate flow (c) formed from the concentrated solvent-containing articles and a flow (e) formed from the diluted permeant flow (d) are obtained, wherein the permeant flow (d) is an inorganic salt solution containing multivalent cations, and the temperature of the permeant flow (d) in the aforementioned first step is 5-60°C.