Web-based media gains more influence through rapid development. Online public opinion becomes an important source of public opinion, and also becomes a new issue attracting more research attention. The paper discussed the character of web-based media communication. According to the difference of information source, three types of web-based media are distinguished. The effect of each type is discussed. At last, the typical issue of "Deng Yujiao" is introduced and analyzed. The different effect of different media on online opinion construction is shown. Based on the analysis, it is possible to detect the trend of certain issue and to help us make decision.
