This strain is a humanized model of the mouse Pdl1 gene in which the gene sequence encoding the extracellular domain (immunoglobulin V-like, IgV-like) of mouse PD-L1 protein is replaced with the corresponding human PD-L1 gene sequence. B6-hPDL1-V mice can be used for the research of PD-L1 targeted drug development screening, efficacy and safety evaluation, tumor immunotherapy evaluation, and immune system mechanisms.