The present invention belongs to the field of tumor therapy and molecular immunology, and relates to a PDL-1 antibody, a pharmaceutical composition thereof and use thereof. In particular, the present invention relates to a PDL-1 monoclonal antibody or an antigen-binding fragment thereof, wherein the monoclonal antibody has a heavy chain variable region comprising CDRs as set forth in SEQ ID NOs: 15-17; and/or has a light chain variable region comprising CDRs as set forth in SEQ ID NOs: 18-20. The monoclonal antibody of the present invention can bind to PDL-1 specifically, and specifically remove immunosuppressive function of PDL-1 and activate T lymphocytes.