Abstract：The prevention of systemic financial risk is an important work to ensure the normal operation of the economy.The effective measure of cross-border capital flows is the basis of stabilizing the exchange rate and foreign exchange market,and formulating the long-term mechanism of financial supervision.This paper uses six different measures to describe the law of China's 2001-2016 year cross-border capital flow.Finally,principal component analysis is used to identify the correlation between different measurement methods in order to determine the validity of China's capital flow measurement.The empirical results show that the total scale method,the real interest rate difference method and the Haque-Montiel method have higher explanatory power for China's capital flow measurement.The real interest rate difference method and Haque-Montiel method are rooted in interest rate determination model.Interest rate regulation should not only be based on the difference of vertical level,but also involve the interest rate difference between the main trading countries horizontally.And monitoring scale indicators include not only single aggregate indicators,but also capital inflow and outflow indicators of various sub-projects,especially capital flows such as equity and trade credit flow,so as to effectively prevent and control financial risks.

Keyword：Cross-border Capital Flows; Measurement of Capital Flow; Principal Component Analysis; Financial Risk Prevention ;