In recent years, the systemic risks of China's stock market has broken out frequently. Many scholars believe that leverage is an important factor that affects systemic risk. Based on Acharya(2010)，this paper studies the relationship between leverage, Marginal Expected Shortfall and Systemic Expected Shortfall of stocks in China under the background of the global financial crisis in 2008, the COVID-19 epidemic in 2020 and the Federal Reserve's interest rate hike as well as the Russia-Ukraine conflict in 2022 respectively. The results show that: in the global financial crisis in 2008, and under the Russia-Ukraine conflict as well as Federal Reserve's interest rate hike in 2022, stocks with higher leverage and higher Marginal Expectation Shortfall will have greater Systemic Expected Shortfall; However, due to "supply-side reform" and "deleveraging", the effect was not significant under the COVID-19 epidemic in 2020. In addition, the manufacturing industry has performed significant heterogeneity under the two shocks in 2020 and 2022.
