Abstract: Pre-understanding is the precondition of understanding. Without pre-understanding, there will be no understanding, let alone accepting of text. Pre-understanding doesn't make text acceptation to be a reader' private affair but ensures understanding and acceptation to be a process of integration of difference with unity. Wechat Public Opinion, as unofficial opinion, is built on information-lower-middle class and has a special pre-understanding and perspective. Official opinion guidance on unofficial opinion, after all, is guidance on the information-lower-middle classes' pre-understanding and implements socialist core values. Neglect of guidance for information-lower-middle classes leads to mismatches between official and unofficial opinions. As a result, official opinion loses validity. Official opinion can work by way of understanding and grasping information-lower-middle class' pre-understanding, reconstructing pre-understanding of traditional media and guiding Wechat public opinion to spread socialist core values. Naturally, there is a dialogue between the two opinions.