Civil rights consciousness prompts the activeness of citizens in participating in the public affairs. And because of the close correlations between the public affairs and the public rights, citizens volunteer actively to take part in the public affair discussion. As an important channel for citizen participation, the media and the information about opinions play important role in intervening and promoting local public affairs’ development. This paper takes the event “Debate on the Construction of Baiyunshan Tunnel in Guangzhou” as case study, aims to discuss how the opinion information is presented on different media platform., who is the main body of the opinion information, and what the key factors affect the intervention and participation of public affairs.