In order to cope with the spread of rumors on Internet and the occurrence of gathering behavior, which may endanger public security and social governance in public emergencies, the author established a database using the data collected from a Sina Weibo official account 'Weibo Rumor Refuting' from January 19 to February 19, 2020. Nvivo was used for data coding and analyzing, by which it was found that rumors circulating in public emergencies bear obvious characteristics of localization and high reproducibility, and could be disguised as of administrative power. On the basis of previous studies and taking into consideration the peculiarities of public health emergencies, the author believes that improving the communicating mode of refuting rumors, regenerating expression strategy of refuting rumors and establishing communicating mechanism with rumor-involved Web-bloggers are key measures to be taken to reconstruct social order and help to repair social trust in a risk society.