Abstract: The COVID-19 epidemic-related rumors refuted by China Internet Joint Rumor Platform is selected as the research object and content analysis is adopted as the research method to analyze the text characteristics of these rumors on five dimensions: the subject of the rumors, the involved objects, the supporting evidence, the content claim, and the expression of the rumors. The study finds that rumors are good at using audience psychology, strengthening importance and proximity, showing the interweaving of authority and vague expression, mixing authenticity and falseness of information to cause difficulty in distinction, and creating a rational and cool-headed discourse. It is proposed that the government, experts, media and rumor-refuting organizations jointly build platforms for information release and rumor management and that the government, media and the public work together to reduce the time and space in which rumors breed and manage internet rumors in case of sudden major public health events.