In recent years，the information technology industry in our country has been developing rapidly. The development of information science technology and the Internet platform provides a new opportunity for the development of social situation perception. It can be helpful to make up for the limitations of traditional research methods through the network data used to compute user psychological factors. In view of this，the network data is the ideal way of social situation perception research，and is a rapid trend to establish subjective social situation analysis system. This report focuses on Sina “micro-blog” platform. Through the online data acquisition of large-scale social network user，the features of user online behavior，the content of online text are extracted. Facing to Beijing area，this report carries out the computation of public attitudes during different events. Results show that，the system can figure out the public social situation timely before and after the event，and provides data support for the formulation of public policies.