CXCR4 is a member of chemokine receptors and plays a vital role in numerous diseases and cancer processes, which makes the CXCR4/CXCL12 chemotactic axis a potential therapeutic target. In this study, we used lentiviral vectors as a novel technology to produce a monoclonal antibody against CXCR4. Lentivirus vector pLV-CXCR4-Puro was successfully constructed and a hybridoma cell line 1A4 was generated. The CXCR4 monoclonal antibody (MAb) 1A4 had high titer and affinity, and the isotype was identified as IgG1a. The recombinant lentivirus vector could effectively stimulate the production of 39 kDa CXCR4 antibody in vivo after immunization. Western blot analysis showed that the MAb could recognize the CXCR4 antigen expressed on transfected 293T cells as well as various human cancer cell lines. Immunofluorescence assays showed that MAb 1A4 mainly localized and strongly stained on the membrane of transfected 293T cells. Immunohistochemistry assays demonstrated that 1A4 could recognize strong expression of CXCR4 on the hepatocellular carcinoma (HCC). Thus, the method using lentiviral vectors may have application on effective and large-scale production of the CXCR4 monoclonal antibody, which will be a potential tool for the diagnosis and treatment of human cancers.