Grassroots opinion leader，with the identity of spokesperson of netizens，is the typical feature of public opinion group in the network times，and it is a new problem for network public opinion guidance to face and deal with in the new situation.The main role of TuFu in the opinion of network public emergencies is：driving the network opinion to the climax；triggering another round of public opinion wave when the opinion fades.Reasons of TuFu playing the role of opinion leader mainly lie in the followings：making speeches at any time when he participated in public emergencies.He was a active person in the forum，and then took part in protecting public rights，which helps him win certain popularity.The Commentary position and thinking framework of his article is always standing by the position of the disadvantaged，questioning local public power in the frame of legal framework.The way to prove his opinion is mainly irrational logic inference，which make him easy to heed and trust only one side.The style of his prose is colloquial expression and pay attention to communication with net friends.Research of function mechanism of TuFu as an opinion leader is of inspiring significance to the network public opinion guidance of the Government.