With increasing attention paid by the state to the popularization of science for earthquake prevention and disaster reduction, the construction of natural disaster monitoring and early warning system, and the modernization of natural disaster prevention and control system and capacity, great progress has been made in China on public understanding of the earthquake prevention. The 5.1 magnitude earthquake occurred in Tangshan city on July 12, 2020 was an aftershock of the great Tangshan earthquake in 1976, and has drawn great attention and discussion. Based on this event, this study carried out science popularization and field research on relevant earthquake disaster knowledge, by conducting a questionnaire survey on earthquake disaster knowledge in Lunan District of Tangshan and the suburb of Fengnan District, and interviewing the Tangshan Earthquake Agency. Through the data cross analysis of the questionnaire results, the study provides a general estimate of the public understanding of the earthquake, which will be reported to the local government.