Abstract: The advancement of the network technology facilitates the dissemination of information through all kinds of media, and provides conditions for the public opinion of “emotion over truth”. The authority of mainstream ideology has been constantly challenged because of the overwhelming false media reports in“post-truth”era. The present “post-truth” situation misleads college students who are immersed in cyberspace about “emotion over truth”instead of making objective judgement, and poses a big challenge for cyberspace governance. Therefore, it is vital to tease out the underlying causes of university cyberspace governance chaos in the “post-truth” era, and try to solve the problem by constructing rational ideology, optimizing algorithm push, promoting mainstream ideology, and governing course resources.