Abstract
The USA and China have been the leading trade and investment partners of Vietnam for a long time. Since the end of 2019, the Covid-19 pandemic, which originated from Wuhan - China, has spread on a large scale, had an impact on the stock markets of Vietnam, China and the USA, as well as the relationship among those markets. The Copula method is used in this study to investigate the dependence structure between Vietnamese stock market and, respectively, the USA and the Chinese stock markets during the Covid-19 pandemic. The research results confirm that before the pandemic, the dependence degree between the Vietnamese stock market and each stock market the USA or China stock markets are weak. However, the Covid-19 pandemic has increased the dependence degree between the Vietnamese stock market and each of the two leading stock markets in the world sharply.
