Under the background of COVID-19 epidemic, the legal governance of network rumors is the need of epidemic prevention and control. It is also the basis for implementing the strategy of governing the country according to law and constructing the social governance mechanism of "co-construction, co-governance and sharing". The spread of COVID-19 epidemic rumor is characterized by three dimensional channels, fragmented content, real-time spread speed and diversified motives. There are some problems in rumor governance, such as insufficient punishment, one-way government-led rumor control, unclear boundaries between freedom of speech and Internet rumors, "Tacitus trap" and "new spreading of old rumors". Based on the relationship between law and policy, the idea of multi-dimensional co-governance concept, principle of proportion, and popularization of law and technical governance, this paper proposes to improve the legislative level and systematization degree of Internet rumor governance, cultivate the participation mechanism of multiple subjects under the guidance of the government, standardize the modesty of the judicial governance of rumors, strengthen the construction of anti-rumors platform and early warning mechanism under technical means, and establish transparent information and open social communication mechanism, so as to maintain the positive aggregation effect of public opinion.