This kit is based on one-step RT-PCR technique. In practice, M region of Influenza A virus, M region of Influenza B virus and the highly conserved regions of 2019 novel coronavirus N and ORF1ab are selected as amplification target regions, and design specific primers and fluorescent probes respectively. Combined with reverse transcriptase and hot-start enzymes to form nucleic acid amplification reagents, use a fluorescent PCR instrument for PCR amplification, and detect fluorescent signals to perform the qualitative detection of influenza A virus (FAM), influenza B virus (TexasRed), and 2019 novel coronavirus (VIC) in unknown specimens. At the same time, use the house-keeping genes as the internal standard (CY5) to design specific primers and probes for amplification, which can monitor the specimen collection and nucleic acid extraction process to reduce the occurrence of false negative results.