Reverse repurchase refers to an operation in which the central bank sells treasury bills, short-term credit bonds, central bank bills and other money market instruments, and at the same time promises to repurchase these instruments within a certain period of time in the future, thereby obtaining funds. Simply put, reverse repurchase is when the central bank obtains funds by selling financial instruments while committing to repurchase these instruments in the future. The main purpose of reverse repos is to stabilize the money market and control liquidity. If there is excess liquidity in the banking system, the central bank can sell money market instruments through reverse repurchase and other methods to recover liquidity and reduce the money supply in the market, thereby curbing inflation. Conversely, if there is insufficient liquidity in the banking system, the central bank can inject liquidity into the market through reverse repurchases and other methods, thereby promoting economic growth and the development of financial institutions. Reverse repurchase is an important monetary policy tool of the central bank and is of great significance to financial markets and economic stability.