As social stabilizer and ballast stone，middle class is becoming the main force in the front of the network public opinion in China. On the subject of collective voice of middle class，this paper researches characteristics of the middle class in the network society，comb the diachronic evolution of middle class’ collective voice，analyze its effects on public opinion and governance，and put forward some suggestions of guidance strategies. Studies have shown that the middle class still has considerable network discourse in spite of the proportion in the overall internet users is diluted，with the increase of internet penetration rate and internet spreading to all sectors of society. Marked by the event of Sun Zhigang，Xiamen PX incident，Wenzhou high-speed train accident，a series of incidents taken security as the key words since the year of 2016，and the middle class made collective voice on the network stage several times，showing the huge impact on public opinion flood. In this regard，the relevant departments should strengthen supervision of the key issues and key media，make the media and opinion leaders play a positive role，protect the legitimate rights and interests of the middle class，and guide the middle class from the “backyard” to the public sector and public rights，etc.，so as to govern the middle class public opinion scientificly.