The phenomenon of fake news has a long history，and its emergence，interpretation and change are part of the changes of social information ecology. However，there are still differences in the understanding of the concept of fake news. Based on the analysis of the existing academic literature，this paper discusses the concept，history，academic practice and controversy of fake news. The academic research on fake news mainly focuses on its causes，characteristics，effects，governance and so on. Many interdisciplinary theories have been applied to the study of fake news，forming a complete research system. However，with the advent of the Internet and the development of social media，the concept of fake news，mode of production and social impact have also changed. There is still room for improvement in the definition and countermeasures of fake news. At the same time，it is also very important to clarify the concept boundary and the relationship with other similar concepts for the cognition of fake news.