The currency in Korea is the won. Korean bank notes are issued in four denominations: 1,000 won, 5,000 won, 10,000 won, and 50,000 won. To get around the lack of large bills, bank-issued "checks" are often used. These checks are not personalized and function much like cash, except that identification is required to spend them. There are four coins: 500 won, 100 won, 50 won, and 10 won.
 

Traveler's checks are accepted at all charted banks ("eunhaeng" in Korea). Foreign debit cards are not accepted. some major banks have ATMs that accept international credit cards. Most ATMs that can be used to draw money offer English instructions. Major foreign credit cards (VISA, MasterCard, American Express) are widely accepted by hotels and other tourist facilities and are generally regarded as safe to use.

When transferring funds from Korea to abroad, a local bank will place a stamp in your passport stating how much was transferred, in keeping with Korea's Foreign Currency Control Act. If you are working in Korea and paying Korean income tax, you can transfer you to entire income based on your tax payment certificate. As a tourist, you are required to declare at customs if you are bringing into, or carrying out of the country more than the equivalent of US$10,000, including local currency.

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www.visitkorea.or.kr