Tobacco (Nicotiana tabacum) is an important leaf economic crop. Narrower and thicker upper leaves are the primary cause of its lower usability in southwest China. ANGUSTIFOLIA (AN) gene controls the polar elongation of leaf cells in leaf width direction and the trichome-branching pattern in plants, which will play an important role in improving width and thickness of leaves. Therefore, characterisation of a member of the AN subfamily, NtAN, from Nicotiana tabacum will be crucial to increase usability of upper leaves. In this report, we cloned two cDNAs and the genes of tobacco (Nicotiana tabacum) AN (NtAN) which originated from diploid species N. tomentosiformis (NtAN-T) and N. sylvestris (NtAN-S), respectively. The full-length cDNA of NtAN-T is 2,288 bp and contains a 1,893 bp ORF that encodes a protein of 630 amino acids. The 5’ and 3’ UTR are 132 and 262 bp in length, respectively. NtAN-T gene has a length of 5,537 bp, and consists of seven exons and six introns. They are 2,800 bp in length cloned in the gene’s 5’ flanking region. The full-length cDNA of NtAN-S is 2,410 bp and contains a 1,899 bp open reading frame (ORF) that encodes a protein of 632 amino acids. The 5’ and 3’ untranslated regions (UTR) are 127 and 384 bp in length, respectively. NtAN-S gene has a length of 5,529 bp, and consists of seven exons and six introns. They are 2,322 bp in length cloned in the gene’s 5’ flanking region. The NtAN-T and NtAN-S shows 54.9% and 67.8% identity to an AN orthologue from Arabidopsis thaliana (L.), respectively. These results will provide important an base for the AN gene’s function on leaf width regulation in tobacco.