In view of the current trend of the epidemic, there is no possibility of infection with novel coronavirus by opening windows and ventilating the air, but there is a risk when high concentration of viral aerosol collects in the outdoor air. According to the 9th edition of the Novel Coronavirus Pneumonia Prevention and Control Program, the main modes of transmission of Novel Coronavirus Pneumonia are respiratory droplet and close contact. Novel coronavirus can be transmitted via aerosols in relatively closed environments, and infection may also result from contact with objects contaminated with the virus. In daily life, sleeping with the windows open at night is virtually impossible to cause infection. However, in some extreme cases, such as when aerosols in the outdoor air contain large amounts of the novel coronavirus, there is a possibility of infection, but the probability of this is almost nil under the outbreak prevention and control measures. Instead of worrying that sleeping with the windows open will transmit the new coronavirus, we should do a better job in our daily lives to protect ourselves, such as wearing masks correctly, avoiding crowded and airtight areas, and washing our hands frequently to minimize the possible risks. Tip: In this article, the terms “new coronavirus pneumonia” and “new coronavirus pneumonia” were renamed to “new coronavirus infection” on December 26, 2022, as announced by the National Health Commission.