Objective The aim of the study was to study the effect of government interventions on the positive rate of influenza detected in Guangzhou First People's Hospital during the outbreak of COVID-19, and to provide a basis to develop prevention measures against influenza and a reference for the indirect evaluation of the preventive effect of COVID-19. Methods Influenza antigen detection data of Guangzhou First People's Hospital were collected retrospectively from 23rd of the 12th lunar month to 15th of the 1st lunar month in 2018—2020, and the positive rates of influenza antigen detection before and after the government intervention were analyzed and compared. Results The positive rates of influenza were generally stable in 2018 and 2019 before and after the Spring Festival, where the positive rate fluctuated in the range of 15.6%～46.5% in 2018, and the positive rate fluctuates in the range of 11.9%～30.4% in 2019. The temporal change of the positive rate in 2020 was different from that of the previous two years. The positive rate curve was relatively stable before the fourth day of the first lunar month, maintaining a range of 20.0%～44.1% in 2020. After the fourth day of the first lunar month, the curve showed a significant downward trend. On the 12th and 15th day of the first lunar month, the positive rate of influenza became 0. Furthermore, the effect of government intervention on the positive rate of influenza showed no gender difference, and the effect was significant for people aged 5～64 years. Conclusion The current government intervention measures against COVID-19 could significantly reduce the positive rate of influenza, prevent the occurrence of influenza, and provide indirect evidence for the prevention of the spread of COVID-19, which was also mainly spread by respiratory tract.