2012 is the year when microblog developed stably，microblog continues to maintain the tremendous influence of public opinion market in China. This report researches the overall situation of microblog in 2012. On the basis of that，the report analyzes the influence of microblog systematicly from many aspects in this year，including its relation to public opinion，policy making via internet，enterprise marketing，traditional media，opinion leader，rumor，social mobilization，and social life style，and then predicts the development trend of microblog in 2013.