The payment and settlement system means the systemic mechanism which clears and settles any debts derived from any economic activities by transferring monetary values. The Payment system in Korea consists of large value funds transfer system being operated by the central bank, net settlement system, securities settlement system and foreign exchange settlement system. Though the payment system play a role as a important infrastructure for the financial stability by transferring every payment funds, the payment system is vulnerable to a serious breakdown when the system meets obstacles because of any participant`s defaults or any computer net is paralysed by the worker`s strikes. The payment system is one of the important infrastructure including financial system, financial business and financial markets. Therefore the operation of stable and efficient payment system has deep relations with financial stability. In reference to these subjects, the Bank for International Settlement (BIS) enhances the standard of requirements to central banks concerning the operation and oversight of payment system. Recently, against the increase of interrelation between the inside and outside of the country and the rapid increase of payment volumes, the problem of system risks has been seriously recognized and the importance of oversight of payment system by the central bank has been emphasized. Consequently, many countries is tending to enable the central bank to oversee the payment system clearly by revising the related regulations and central bank`s acts. The revised Act of the Bank of Korea of 2003. 9. enabled the Bank of Korea to operate and oversee the payment system generally to achieve the stability and efficiency of the payment system. This articles touches and introduces the payment system and regulations related in Korea, the relation between the central bank and the payment system and the oversight system of the payment system in major countries and Korea.