Abstract: Nicotinamide adenine dinucleotide is important to the health of animals and humans. Nicotinamide Mononucleotide Adenylyltransferase 1 (NMNAT1) gene has been characterized to be required for nicotinamide adenine dinucleotide biosynthesis. In present experiment, the complete mRNA sequence of tobacco NMNAT1 gene was amplified using the rapid amplification of cDNA ends methods. The full-length tobacco NMNAT1 gene mRNA was 1,445 bp containing a 753 bp open reading frame which encodes a protein of 250 amino acids. BLAST analysis revealed that tobacco NMNAT1 protein shares high homology with the NMNAT1 of Lycopersicon esculentum (87%), wine grape (65%), soybean (65%), cacao (65%) and barrel medic (62%). Results also showed that tobacco NMNAT1 gene has a closer genetic relationship with the NMNAT1 gene of lycopersicon esculentum. The expression profile was studied and the results indicated that tobacco NMNAT1 gene was highly expressed in leaf. These results established the primary foundation of utilizing tobacco nicotinamide adenine dinucleotide or NMNAT1 as drugs for animals and humans in the future.