Abstract: In order to find out the information of carbonic cnhydrase (CA) genes in tobacco and explore their functions, the members of common tobacco CA family were identified from the tobacco genome database, and the physical and chemical properties, genetic evolution, gene structure, conserved motifs of proteins, cis-acting elements and tissue expression patterns were analyzed. The results showed that there were at least 9 alpha and 6 beta subfamily members in tobacco. On evolutionary relations, lower sequence homology was observed between different subfamily members. Compared with rice, CA members between Arabidopsis thaliana and common tobacco are more closely related. Subcellular localization analysis showed that tobacco alpha subfamily members were distributed in cell wall, cell membrane, mitochondria, chloroplast, cytoplasm and other organelles, while beta subfamily members were present in chloroplast. The analysis of gene structure and conserved motifs showed that the gene structure and conserved motifs of proteins of each subfamily were highly consistent. Analysis of the cis-acting elements of the promoter showed that the promoter of the carbonic anhydriase genes in tobacco contains several cis-acting elements involved in light reaction, hormone response, abiotic stress and mechanical damage. The expression pattern analysis confirmed that the expression levels of carbonic anhydrase genes in different subfamilies of tobacco were different in different tissues and showed the specificity of time and space. The results of this study laid a foundation for the functional study of tobacco carbonic anhydrase genes.