Deoxyribonucleotide (DNA) from salmon testes was successfully extracted by reversed micelles that are formed by a cationic surfactant in isooctane, The degree of extraction of DNA was strongly influenced by the type of surfactant in the organic solvent and ionic strength in the material aqueous phase. The driving force of the DNA transfer was electrostatic interaction between cationic surfactants and negatively charged DNA. Cationic surfactants possessing two long-alkyl chains are one of the best candidates for the successful transfer of DNA from an aqueous solution to a reversed micellar solution.