To grasp the formation of public opinion on the internet，to master the laws of its development，the changes of pattern and the function，to explore the relationship with society，this paper is based on systematic and empirical analysis that makes a detailed analysis about 672 major network public opinion cases occurred from 2003 to 2014.Firstly，the research dimensions of network public opinion cases are as follows：the number，type，spatial distribution and groups. Secondly，we summarize its dissemination in the aspects of disseminator，audience，content，channels and the effect. Finally，this paper outlines the following dissemination features and trends：in the context of new media，disseminators and audience present compound. And channels are different and wide with various content. What’s more，the dissemination effect is totally dominant. As a result，a new “media spectacle” will be created through the dissemination of information in virtual space or with the action and participation in the realistic society.