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Accurate determination of Se in tea is critical for the quality control and safety of Se supplements. In this paper, we developed a rapid and automatic method for the determination of Se in tea samples using mixed acid (VHNO3:VHClO4 = 4:1) digestion followed by ion exchange chromatographic separation coupled to high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) measurement. The radionuclide 75Se was used as a tracer to monitor the loss of Se during entire separation procedure. The application of an automatic separation system speeded up the separation procedure and shortened the entire analytical time to less than 3 h. High performance liquid chromatography measurement of the sample solution after acid digestion shows the species of Se in the digests was Se(VI). 20 mL of HNO3 (> 5 mol L−1) can effectively elute Se from the column, and ~ 95% of Se can be eluted using 20 mL of 6 mol L−1 HNO3. The decontamination factors of more than 1 × 106 were achieved for the major interfering elements (Ca, Zn and Cu) by forming polyatomic ions for mass spectrometric measurement of 82Se by HR-ICP-MS. Meanwhile most of Br can be also removed and the key interference of 81Br1H+ was significantly suppressed in the HR-ICP-MS measurement of 82Se. The average chemical yield of 75Se was 93.2 ± 0.5%, which fall within 95% confidence interval. The developed method was validated through the analysis of certified reference materials, the measured values are in a good agreement with certified values, confirming the analytical method is reliable and accurate. The method established in this work has been successfully applied for the analysis of some commercially available tea leave samples. [ABSTRACT FROM AUTHOR]