The antigen test, Neocoronavirus Antigen Test, has a faint line indicating a negative result, which may be related to factors such as short observation time and improper operation. It is normal for some people to have a faint line indicating a negative test result when doing the NeoCoronavirus antigen test. If people observe the test result immediately after the test, a faint line may appear, and over time, the line may deepen or even appear as two bars. A faint line may also appear if the antigen test kit is used improperly. For people with a very faint antigen test line, if they have recently been exposed to patients with novel coronavirus pneumonia or with fever, cough, or body weakness, they should report to the community or consult the local sentinel hospitals for further nucleic acid test and lung CT to confirm whether they are infected with novel coronavirus. It is recommended that people follow the instructions for antigen testing, and those with abnormal results should seek prompt medical attention. Daily attention to open windows and ventilation, appropriate exercise, avoid close contact with others. Tips] In this article, “new coronavirus pneumonia” and “new coronavirus pneumonia” have been renamed to “new coronavirus infection” on December 26, 2022, as announced by the National Health Commission.