Abstract: In order to further confirm the interactive relationships between virus and its host, a gene featured the characters of m-type thioredoxin in tobacco cell was cloned by homologous alignment and named as Nt Trm. The expression of Nt Trm and its relationship with PVY accumulation were studied by protoplast transient transformation, virus-induced gene silencing(VIGS), semi-quantitative RT-PCR and Northern blot test technologies. The results showed that the expression of Nt Trm in leaves of cv.Honghuadajinyuan was obviously up-regulated 10 days after PVY inoculation; the down-regulation of Nt Trm significantly promoted the accumulation of PVY in leaves of Nicotiana benthamiana; while the over-expression of Nt Trm in tobacco protoplast obviously inhibited the accumulation of PVY viral RNA. It preliminarily indicated that NTtrm could be induced by PVY infection and its up-regulated expression might affect the PVY infection in tobacco cells.