Background and Aim : Due to the recent coronavirus epidemic and the widespread spread of COVID-19, the importance of studying coronaviruses, especially in the field of their molecular characteristics, became more clear Based on pervious archives, the first disease related to the coronavirus recorded so far was probably related to animals. However, the most evolutionary studies focused on S1 gene, Survey on other gens of coronaviruses such an N gene, that is important in immune responses against virus, could be very helpful. Methods : Human, porcine, rodent, avian, bovine, feline, Canine, and bat coronavirus N genes were collected from the gene bank (NCBI database). After the alignment of N gene of all used coronavirus sequences, using Mega X software (version 11), the similarity rate between the N gene sequences of human and animal coronaviruses was determined. Then, phylogenetic tree was drawn based on N gene sequences. Results : According to the results, the rate of nucleotide similarity was shown about 92-95%. The highest similarity was between SARS-CoV is WGS-36 and bat coronavirus BM48-31 and the lowest similarity was related to bat coronavirus BM48-31 and another used isolate SARS-Cov. Based on the evolutionary tree, human SARS coronaviruses grouped together with a bat coronaviruses and rodent coronavirus and also three bovine coronaviruses while some other bat coronaviruses were clustered in other group distinct from SARA-Cov. Conclusion : Evolutionary studies of different genes of various coronaviruses specially which has notable role in immunity against the viruses could be significant to control the disease and design effective vaccines. Also, different similarity rates between SARS- Cov isolates and bat coronavirus BM48-31 could be explain the possibility of mutations in the N gene of coronaviruses
