Provided is a single-chain antibody TRsAbl against ToRSV, having an amino acid sequence shown in SEQ ID NO.1, and consisting of a 15aa histidine tag region, a 180aa ToRSV heavy chain variable region, a 15aa linker peptide, and a reverse-linked 117aa ToRSV light chain variable region, connected in sequence, with a length of 327 amino acid residues. The sequences of the 180aa heavy chain variable region and the 117aa light chain variable region are derived from the sequence of a monoclonal antibody produced by the hybridoma cell line CGMCC18321. The yield of TRsAbl, obtained by a whole gene synthesis method, is 200-2000mg/L, with a purity of 82-95%. The single-chain antibody TRsAbl has the characteristics of selectively identifying the peptide QAAQQAGKNPFGRG in the ToRSV coat protein, and has a positive response to natural ToRSV particles. The invention has broad application prospects in the Entry-Exit inspection and quarantine of the ToRSV.
