Abstract: The sample of sea shellfish was digested with HNO3 and H2O2 with microwave assisted heating, and the content of Se in sample solution was determined by HG-AFS. Hydride of Se ion was generated by reacting with 10 g·L-1 KBH4 solution (dissolved in 5 g·L-1 KOH solution). The interference of HNO3 was eliminated by adding ascorbic acid. Under the optimized experimental conditions, linear relationship between the fluorescence intensity and mass concentration of Se was kept in the range within 600 μg·L-1, with detection limit (3s/k) of 0.076 μg·L-1. Test for precision was performed with 2 μg·L-1 Se standard solution, the value of RSD (n=11) found was 1.6%. The proposed method was applied to the analysis of 4 substantial samples, giving values of recovery found by standard addition method in the range of 86.0%-116.0%.