Objective：This study aims to examine the effects of signal transducer and activator of transcription 3（STAT3） on the transcription and expression of programmed death ligand 1（PD-L1）gene in human glioma cells and screen the possible STAT3-binding elements within PD-L1 gene promotor. Methods：U251 cells were cultured and treated with STAT3 inhibitor（BP-1-102） or DMSO. The expression of PD-L1 protein on the surface of U251 cells was examined by flow cytometry after 9 h. The luciferase reporter plasmid of full-length PD-L1 gene promotor（pGL3-PD-L1-FL）was transfected into U251 cells，and then cells were treated with BP-1-102 or DMSO. The luciferase activity in U251 cells was examined after 9 h. The luciferase reporter plasmids of full-length or truncated PD-L1 promoter（pGL3-PD-L1-FL，pGL3-PD-L1-1，pGL3-PD-L1-2，pGL3-PD-L1-3，pGL3-PD-L1-4）and the plasmid of pCMV-STAT3 were co-transfected into HEK293 cells. Then，the luciferase activity was detected to screen the STAT3-binding elements. Furthermore，bioinformatics software was used to predict the STAT3-binding elements in the promoter of PD-L1 gene，and mutation experiments were carried out to determine the validity of these binding elements. Results：BP-1-102 could significantly down-regulate the gene transcription and protein expression of PD-L1 in U251 cells. In addition，the plasmids of pGL3-PD-L1-FL or pGL3-PD-L1-1~4 and pCMV-STAT3 were co-transfected into HEK293 cells，and then the luciferase activity in different groups was determined. The result displayed that the activity of pGL3-PD-L1-4 was much lower than that in others，indicating that the region of PD-L1 promoter（-200~0 nt）might contain STAT3-binding elements. Bioinformatics software predicted that the region might contain two STAT3-binding elements，that are located at -194~-184 nt and -135~-125 nt. Further studies revealed that mutation of -194 ~-184 nt and -135~-125 nt elements especially the combined mutation could significantly down-regulate the luciferase activity of pGL3-PD-L1-FL. Conclusion：STAT3-binding elements within PD-L1 gene promotor were successfully screened out，which could be beneficial to further studies about the STAT3-related transcription regulation of PD-L1 gene in glioma cells.