In this study, we constructed a LentiCRISPRv2/dCas9‐TET1CD‐sgRNAs system targeting specific methylation sites of BRD7 promoter region based on five sgRNAs (sgRNA1‐5), and confirmed that sgRNA2 and sgRNA5‐guided dCas9‐TET1CD system could dramatically reduce methylation level and promote the transcriptional activation and BRD7 expression, thereby inhibiting tumour malignant progression and play anti‐tumour effects in NPC, and the combination of the two sgRNAs exhibited a more pronounced effects. The gene discussed is BRD7; the disease is nasopharyngeal carcinoma.