The combtail fish (Belontia sp.) is a type of fish that lives in groups in river or swamp waters. The combtail fish are included in the Belontiidae family. This family is presented only by genus Belontia and two species Belontia hasselti and Belontia signata. The purpose in this research was to obtain the Cytochrome C Oxidase (COI) gene sequences, the percentage of nucleotide identities of coum…