The South Korean won, sometimes known as the Republic of Korea won (symbol: ₩; code: KRW; Korean: 대한민국 원), is the official currency of South Korea. A single won is divided into 100 jeon, the monetary subunit. The jeon is no longer used for everyday transactions, and it appears only in foreign exchange rates. The currency is issued by the Bank of Korea, based in the capital city of Seoul. The South Korean won was first issued in 1949, then was replaced by the South Korean hwan between 1953 and 1962, before the adoption of the current South Korean won in 1962.

The old "won" was a cognate of the Chinese yuan, which was derived from the Spanish-American silver dollar. It is derived from the hanja 圓 (원, won), meaning 'round', which describes the shape of the silver dollar.

The won was subdivided into 100 jeon (Korean: 전; Hanja: 錢; MR: chŏn), itself a cognate of the East Asian unit of weight mace and synonymous with money in general. The current won (1962 to present) is written in hangul only and does not officially have any hanja associated with it.

The Korean won, Chinese yuan and Japanese yen were all derived from the Spanish-American silver dollar, a coin widely used for international trade between Asia and the Americas from the 16th to 19th centuries.

During the colonial era under the Japanese (1910–45), the won was replaced by the Korean yen which was at par with the Japanese yen.

After World War II ended in 1945, Korea was divided, resulting in two separate currencies, both called won, for the South and the North. Both the Southern won and the Northern won replaced the yen at par. The first South Korean won was subdivided into 100 jeon.

The South Korean won initially had a fixed exchange rate to the U.S. dollar at a rate of 15 won to 1 dollar. A series of devaluations followed, the later ones, in part, due to the Korean War (1950–53). The pegs were:

The first South Korean won was replaced by the hwan on February 15, 1953, at a rate of 1 hwan = 100 won.