This paper builds a global bank capital flow network based on the data of cross-border capital flow claims from countries during the period 2000Q1-2016Q4. It empirically examines the impact of US trade policy uncertainty (USTPU) shocks on global bank capital flow network and the role of macroprudential policies. It shows that: (1) The rising USTPU will have a negative impact on the overall network indicators, resulting in a decline in the overall network"s relationship; (2) The rising USTPU will have a negative impact on the cross-border capital flow network indicators of each country in the network, and the use of macroprudential policies in various countries can effectively mitigate the negative impact of US trade policy uncertainty; (3) Trade links between countries and the United States and foreign exchange exposure are important contagion channels for the USTPU that has impacted the global bank capital flow network; (4) After removing the United States from the global bank capital flow network, the rise in the USTPU will have an indirect impact on the bank capital flow network between other countries. At this time, the use of macroprudential policies by countries is still effective, and further verify the macro-prudential policies’ effectiveness of stabilizing domestic financial system. (5) The USTPU will have a heterogeneous impact on countries with different economic characteristics. This paper provides important empirical evidence that the USTPU exacerbates financial risks, and also enriches the policy connotation of macroprudential policies to deal with fluctuations in cross-border capital flows and external shocks.