Objective To explore the effect of blocking BTLA-HVEM (herpesvirus entry mediator-B and T lymphocyte attenuator) pathway on dendritic cell function and the related immunological mechanisms. Methods Murine BTLA extracellular domain eukaryotic expression vector psBTLA was constructed by gene recombination and transfected CHO by Lipofection method. Mouse bone marrow cells were induced to differentiate into DCs by GM-CSF plus IL-4. Expression of BTLA and HVEM on DCs was detected after HSPT0-TC-1 peptide complex stimulation by FACS. Expression of BT-1 and secretion of IL-12 were detected after HSP70-TC-1 peptide complex plus psBTLA transfected CHO culture supernatant stimulation on DCs. Pretreated DCs co-cultured with the same genetic background mouse splenocytes and lymphocytes proliferation and cytokine secretion were detected. Effect of psBTLA gene transfer in vivo on BT-1 expression of DCs and tumor growth on tumor-bearing mice was detected. Results Extracellular domain of murine BTLA was successfully constructed, psBTLA stable transfection CHO cells were obtained and expression of BTLA extracellular domain(sBTLA) was detected the in its culture supernatant. BTLA and HVEM expression of DCs were increased after stimulation by the antigen peptide complex. When DCs were treated with antigen peptide complex plus culture supernatant containing sBTLA, B7-1 expression and IL-12 secretion were increased. Co-cultured with splenocytes, lymphocytes proliferation and cytokine secretion, such as IL-2 and IFN-γ,, were also increased. Gene transfection with psBTLA in vivo promoted B7-1 expression on DCs and inhibited cervical cancer cells growth. Conclusion Blockade of BTLA-HVEM inhibitory pathway with sBTLA can further improve DCs function, activation of lymphocytes and promote antitumor immune response.