Objective To quickly find out the cause of SARS-CoV-2 nucleic acid positive in pharyngeal swab samples of medical staff in a community health service center in Wuhu in August 2021,and improve the precision prevention and control ability of COVID-19. Methods Using real-time fluorescent RT-PCR technology,10:1 pharyngeal swab mixed tube samples (SARS-CoV-2 nucleic acid screening positive by a third-party testing organization) and recollected pharyngeal swab single tube samples from a community health service center were rechecked for SARS-CoV-2 nucleic acid,and SARS-CoV-2 D614G mutation sites were detected in nucleic acid positive samples.Then,smear samples from the environment outside the community health service center were collected for SARS-CoV-2 nucleic acid pollution assessment and detection. Results Two of the three 10:1 pharyngeal swab mixed collection tube specimens were positive for nucleic acid double target (ORF1ab+N),and 35 pharyngeal swab single collection tube specimens of medical staff and medical interns were negative for nucleic acid double target.There was no variation of SARS-CoV-2 D614G locus in the positive samples of mixed collection tubes,which was inferred to be from the wild strain of SARS-CoV-2 (vaccine strain).Among the 12 environmental samples,3 were single target positive,of which 1 was ORF1ab gene positive,which came from the work clothes of COVID-19 vaccinators;Two N gene positive samples came from COVID-19 Vaccination Room keyboard and ordinary vaccination room keyboard and mouse. Conclusion The SARS-CoV-2 nucleic acid positive of pharyngeal swab mixed collection tube samples of medical staff in a community health service center was caused by COVID-19 vaccine contamination.