The won was quoted at 1,162.7 to the dollar at the conclusion of onshore trade, up 1.8 percent compared to previous close of 1,183.6.
South Korean shares hit their highest level since April 28, with foreign stock-buying largely supporting the main board.
The Korea Composite Stock Price Index (KOSPI) closed up 1.3 percent at 2,011.63 points.
Offshore investors bought a net 263.8 billion won ($227.14 million) worth of KOSPI shares for the day.
Steelmaker Posco rose sharply to near 4-week high on hopes of stronger profits and ended up 6.9 percent.