Abstract: The occurrence of emergencies often has a profound public opinion influence, but the public opinion influence of different types of events varies to some extent. Previous studies mainly focus on the analysis of overall attributes of public opinion influence, while there are relatively fewer research results on its classification. So it is of great theoretical significance and practical value to study the public opinion influence of emergencies and its main driving factors from the dimension of event classification. Based on the principles of comprehensiveness, timeliness, totality and scientificity, the paper selects 40 typical emergencies from January to September 2022, classifies and compares them to analyze the commonalities and differences of different types of events, and interprets the nine types of public opinion effects of emergencies. In addition, it evaluates the public opinion influence of 40 typical events by using the VIKOR method, and explores its main driving factors by using factor analysis. The study finds that there are differences in the influence of public opinion on different categories of events, which result from a combination of factors. For instance, military security, international security, epidemic security, public security, and large-scale natural security events tend to have a larger influence on public opinion, while fire safety and transportation safety events have a relatively smaller influence. Additionally, the study identifies that the indirect effect of microblog communication, the emotion-oriented effect, the authority fermentation effect, and the communication hierarchy effect are key driving factors for the influence of public opinion on emergencies.