Canis MitoSNP is a tool allowing assignment of each mitochondrial genomic position a corresponding position in the mitochondrial gene and in the structure of tRNA, rRNA, and protein. The main aim of this bioinformatic tool was to use data from other bioinformatic tools (TMHMM, SOPMA, tRNA-SCAN, RNAfold, ConSurf) for dog and human mitochondrial genes in order to shorten the time necessary for the analysis of the whole genome single nucleotide polymorphism (SNP) as well as amino acid and protein analyses. Each position in the canine mitochondrial genome is assigned a position in genes, in codons, an amino acid position in proteins, or a position in tRNA or rRNA molecules. Therefore, a user analysing changes in the canine and human mitochondrial genome does not need to extract the sequences of individual genes from the mitochondrial genome for analysis and there is no need to rewrite them into amino acid sequences to assess whether the change is synonymous or nonsynonymous. Canis mitoSNP allows the comparison between the human and canine mitochondrial genomes as well. The Clustal W alignment of the dog and human mitochondrial DNA reference sequences for each gene obtained from GenBank (NC_002008.4 dog, NC_012920.1 human) was performed in order to determine which position in the canine mitochondrial genome corresponds to the position in the human mitochondrial genome. This function may be useful for the comparative analyses.