Antigen testing generally refers to the New Crown Pneumonia Antigen Test. In general, the presence of vertical bars on the antigen test paper has no special significance. During the antigen test, attention should be paid to the lines in the “C” and “T” positions. If there are two lines, the result is positive and further nucleic acid testing is required immediately. If there is only a line in the “C” position, the result is negative, and if there is only a line in the “T” position, the test is invalid for some other reason and needs to be repeated. Therefore, the vertical bar in the antigen test does not have the significance of its determination, if the vertical bar, does not rule out the production of test paper in the process of the problem, it is recommended to change the test paper in time, test again, or contact the local community, listen to the advice of relevant professionals. Tip: “New coronavirus pneumonia” and “new coronavirus pneumonia” mentioned in this article have been renamed to “new coronavirus infection” on December 26, 2022, as announced by the National Health Commission.