A humanized monoclonal antibody against the CD34 surface antigen is provided in the present disclosure. The humanized monoclonal antibody includes a light chain variable region and a heavy chain variable region. In which, a nucleotide sequence encoding the amino acid sequence for the light chain variable region comprises a nucleotide sequence which encodes the amino acid sequence of SEQ ID No. 9 or an amino acid sequence with at least 80% sequence identity to the sequence of SEQ ID No. 9, and a nucleotide sequence encoding the amino acid sequence for the heavy chain variable region comprises a nucleotide sequence which encodes the amino acid sequence of SEQ ID No. 10 or an amino acid sequence with at least 80% sequence identity to the sequence of SEQ ID No. 10.