To establish a method for the determination of perchlorate in tea by ultra high performance liquid chromatography and tandem mass spectrometry.Methods The perchlorate residue in tea was extracted with 0.2% acetic acid, and the supernatant was cleaned up with Carb SPE, the detection was performed by ultra high performance liquid chromatography tandem mass spectrometry with internal standard method for quantitative. Results The calibration curve was linear in the concentration range of 0.25-50 μg/L (r²=0.999 6), the recovery was in the range of 95.6%-120.0%, the relative standard deviation (RSD) was in the range of 1.9%-17.5%, and the limit of detection of perchlorate was 2.5 μg/kg.Conclusion The method is suitable for the determination of perchlorate in tea with more simplicity, accuracy and high sensitivity.