This kit is intended to conduct, in vitro qualitatively, the rapid differential diagnosis of main mutation sites P681H and HV69-70del of B.1.1.7 mutant strain, main mutation sites E484K and K417N of B.1.351 and P.1 mutant strains, and their common mutation site N501Y for the cases and clustered cases suspected with SARS-CoV-2-infected pneumonia and other cases required for the diagnosis of SARS-CoV-2 infection, positive for SARS-CoV-2 ORF1ab gene in the sputum and throat swab samples. For the definitions of “cases suspected” and “clustered cases suspected”, please refer to the Diagnosis and Treatment Protocol for Novel Coronavirus-Infected Pneumonia, the Monitoring Protocol of Cases of Novel Coronavirus-Infected Pneumonia and other documents (current version) promulgated by China CDC.