The DNA sequence diversity of Python molurus was investigated using the mitochondrial DNA gene encoding cytochrome b. The nucleotide sequences of complete and partial mtDNA cytochrome b were determined in numerous specimens. Sequence divergence between species and genera was evenly distributed in the cytochrome b gene but rather high compared to reports for other fish species. Phylogenetic analyses on complete cytochrome b were used to study the relationships among the considered species. The molecular phylogeny of sample was determined by analyzing cytochrome b gene sequences. On the basis of position of sequence of the given python sample in the phylogenetic tree, the sample showed closest similarity with Python molurus.