Fake news in public crisis events will cause social panic and affect social stability. However, there is still a lack of prevention mechanics and education practice for fake news in public crisis events in China, and the role of libraries this kind of function has not been taken seriously. Firstly, the concept of fake news was defined, the causes and effects of fake news in public crisis events were analyzed, and then the cases of American libraries in the prevention and response to fake news were studied and experiences were extracted from them. Their practice provides reference for Chinese libraries to respond to fake news, participate in the governance of fake news, and develop related services.