Which is better, antigen or nucleic acid testing, generally refers to the new crown antigen test and the new crown nucleic acid test, antigen testing is an important complement to nucleic acid testing. The antigen test is characterized by its rapidity and simplicity, but it is not a substitute for nucleic acid testing. If the nucleic acid test is negative, accompanied by symptoms such as respiratory fever and within 5 days of the onset of symptoms, it is necessary to test the antigen for 5 consecutive days, and if it is consistently negative, no intervention is required, so the antigen test is a complementary supplement to the nucleic acid test. Antigen is the outer shell of the new coronavirus, and a very small amount of antigen is not likely to give a positive result, and is not as sensitive as nucleic acid testing, which detects the genes of the virus and gives a relatively more accurate result. When the antigen test is positive, it needs to be reconfirmed by nucleic acid test. However, when the nucleic acid test is positive, regardless of the result of the antigen test, the person examined has to take measures as a new coronavirus-infected person or a confirmed patient. People who are at risk of contracting novel coronavirus are advised to choose the appropriate test according to their own situation in order to make a clear diagnosis as early as possible.