Abstract: A sensitive analytical method was developed for speciation of aquatic products of Jiaozhou Bay by ion chromatography hydride generation- atomic fluorescence spectrometry( IC- HG- AFS). Learning the mobile phases,extraction reagents,extraction temperature and instrumental conditions was influence for selenium fluorescence signal value.The sample was extracted by the 1.5 mol / L Kalium hydroxide solution.Using the AS11-HC( 250 mm × 4.1 mm,5.0 μm) anion column,20 mmol / L Sodium hydrogen carbonate solution,2% acetonitrile mobile phase,1.0 m L / min velocity of flow. It could be separated simultaneously in 8 minutes,detecting the Selenocystine( Se Cys),Selenomethionine( Se Met),Se( Ⅳ) and Se( Ⅵ). On the optimized conditions,linear relationships between values of fluorescence intensity and mass concentration of selenium species were found in the same range of 0 ~ 100 μg / L,with the correlative coefficients more than 0.996. The detection limits( 3 s / k) of Se Cys,Se Met,Se( Ⅳ),Se( Ⅵ) were 1.53,1.72,0.30,1.06 μg / L,respectively,and the relative standard deviations( n = 6) for the selenium species were all less than 5%.Applying the present procedure to the speciation analysis of selenium in aquatic products,the spiked recoveries from 86.1% to 105.3% were obtained. The method for the determination of selenium species in aquatic products was accurate,reliable,simple and sensitive,and effectiveness for the scientific evaluation of the quality of aquatic products and to provide technical support forconduct risk assessments.