Tetrathiocyanatocobaltate[II] forms complexes with tertiary amine salts or quarternary ammonium salts which were extractable from aqueous solution by organic solvent. In order to study composition of the complex, the colored crystalline complexes produced were evaluated with elemental analysis, infrared and mass spectra. And also a novel spectrophotometric method for the determination of tertiary amine salt or quarternary ammonium salt with tetrathiocyanatocobaltate[II] was established by organic solvent extraction within coefficient of variation of 1.06-1.35%.