The NtNHX13 gene was successfully isolated by homologous cloning from cultivated tobacco. The CDS length of NtNHX13 was 1 617 bp, and it was predicted to encode a 538amino acid protein. The theoretical isoelectric point of NtNHX13 protein was 8.67, and the molecular weight was 59.34 kD. The bioinformation analysis of NtNHX13 showed that it belonged to membrane protein containing 11 transmembrane regions，and had a conserved amiloride bindingsite specific to NHX protein. The phylogenetic tree analysis showed that NtNHX13 shared the same group with NHX from chicory and chrysanthemum. Tissuespecific expression analysis indicated that NtNHX13 was ubiquitously expressed in roots, stems, leaves and flowers, whereas had the highest level in leaves. The expression of NtNHX13 was upregulated after salt treatment, indicating that it was involved in salt stress response. The expression of NtNHX13 was upregulated in the early stage of topping, which was consistent with the increase of potassium content in this stage. Therefore, it was speculated that NtNHX13 could transport potassium ions from cytoplasm to vacuole.