Abstract：It is of great reference value to study the international linkage and risk spillover effects of Chinese and foreign stock markets under the impact of emergencies to prevent and resolve stock market risks. This article uses the multivariate DCC-GARCH model and the GARCH-Copula-CoVaR model to analyze the international linkage and two-way risk spillover intensity of major stock markets in the world during the four periods of the US subprime crisis，the European debt crisis， the sharp fluctuations of China's stock market in 2015 and the COVID-19 in 2020. The research results show that there are obvious linkages and two-way risk spillover effects in Chinese and foreign stock markets under extreme conditions， and the risk spillover effects of foreign stock markets on Chinese stock markets are more significant. The bigger spillover effect on China's stock market was during the European debt crisis and the sharp fluctuations of China's stock market in 2015， while the spillover effect was relatively small during the COVID-19 in 2020.

Keywords：Stock Market; International Linkage; Risk Spillover Effect