Abstract: Based on the financial reports data of China's forest-related listed companies from 2018 to 2021, the impact of COVID-19 on the operating performance of these companies is analyzed by using regression discontinuity method and LDA topic model. The regression discontinuity analysis shows that the outbreak of COVID-19 has directly led to a significant decline in the operating performance of these companies in the first quarter of 2020. The results of thematic clustering reveal that the main reasons for the decline in business performance include the shortage and rising prices of raw materials such as wood pulp and wood, and the obstruction of domestic and international logistics and transportation. The delay of resumption of production and work caused difficulties in the operation of some enterprises and heavy cost burden. The market demand for forest products was restrained in the short term, and the customer orders were insufficient due to the decrease of consumers' purchase desire. With the gradual consolidation of the effectiveness of domestic epidemic prevention and control, the business performance of forest-related enterprises has gradually warmed up. Through thematic clustering of the corpus of "main factors influencing business performance changes", it is found that the main reasons for the warming of business performance are: after the resumption of work and production, the supply chain has gradually returned to normal operation; capacity allocation is optimized to improve production efficiency; the marketing mode is expanded and the digital process is accelerated. Based on the specific difficulties faced by China's forest-related listed companies and combined with the effective measures taken by some enterprises, this paper puts forward some management suggestions.