Abstract: Objective To explore the inhibitting effect of 1 0-23DNAzyme on the growth of nasopharyngeal carcinoma (NPC) cell,EBV-LMP1both in vivo and in vitro.Methods Thosthorothioate 1O- 23DNAzyme and analogs targetted on EBV-LMP1 (Epstein-Barr virus encoded latent membrane protein 1)gene mRNA were designed and synthesized ,and transfected into C666-1 cells with lipofectamine ,observing the inhibiting effect on LMP1 . Xenografts of NPC in nude mice were formed ,and after DNAzyme and analogs were injected in tumor, the depressive effects on the growth of tumor and LMP1 gene were assessed.Results The results showed that DNAzyme inhibited the expression of LMP1 gene in vivo and in vitro ,and also the growth and metastasis of xenograft of NPC were depressed,and it was found that the effect of DNAzyme, was better than that of its analogs. （P〈0.05）. Conclusion 10-23DRz can strongly block the expression of EBV-LMP1gene in the C666-1 cell model and xenograft in nude mice .It might serve as a specific and effective anti-LMP1 gene therapeutic candidate agent．