After the victory of the Anti-Japanese War, Zhu Ziqing still taught in Tsinghua University. 1In June, 948, he participated in a demonstration against American support for Japan in Beijing, and signed the Declaration on Protesting American Policy of Supporting Japan and Refusing to Accept American Flour. The declaration said that it resolutely refused the "aid" of the United States and did not accept American flour. At that time, Zhu Ziqing suffered from a serious stomach trouble. His body is very thin, weighing less than 40 kilograms. He often vomits and even can't sleep all night. Refusing to receive relief powder means that life is more difficult. He wrote in his diary: "I firmly believe that my signature is correct." Because we oppose the US policy of arming Japan, we should not shirk our responsibilities if we want to take direct action. " Two months later, Zhu Ziqing died of poverty due to illness.