Sports events are the core of the sports industry. The COVID-19 had a significant impact on sporting events，many sports events，including marathons，were shut down. In the second half of 2020，sports events were gradually resumed，and marathons and other large-scale mass sports events were be held successively. As the only stop of the national marathon championship and Tokyo Olympic Games under the normal condition of epidemic prevention and control，2020 Nanjing Marathon has its research significance. This paper takes the 2020 Nanjing Marathon as the research object，based on the analysis of event operation and management，sponsors and media industry，analyzes the development status and brand value of the event，mainly including three aspects：event management，operation service and brand communication.