Fuente: WIPO "tobacco agriculture" The invention discloses a tobacco NtSLAH3 gene mutant as well as a molecular identification method and application thereof. The tobacco NtSLAH3 gene mutant is NtSLAH3-1, C at the 487th site of a tobacco NtSLAH3 gene is mutated into T, a termination codon is formed, and the gene is terminated in advance; and a nucleotide sequence of the gene mutant NtSLAH3-1 is as shown in SEQ ID NO.2. The tobacco NtSLAH31 gene mutant, the molecular identification method and the application are provided for the first time through systematic research, according to a tobacco plant obtained through the NtSLAH3 gene mutant NtSLAH3-1 capable of reducing the chlorine ion content in the tobacco leaves, the chlorine ion content in the tobacco leaves is reduced by 62.9% compared with a control group, and the chlorine ion content in the tobacco leaves is remarkably reduced.