Bisulfite sequencing, qRT-PCR, immunohistochemistry staining of the NPC clinical samples and addition of methylation inhibitor, 5’azacytidine, in NPC cells were performed to verify the correlation between DNA hypermethylation and expression of CLDN11. Promoter reporter and EMSA assays were used to dissect the DNA region responsible for transcription activator binding and to confirm whether DNA methylation could affect activator’s binding, respectively. This evidence concerns the gene CLDN11 and nasopharyngeal carcinoma.