An ultra performance liquid chromatography-tandem mass spectrometric(UPLC-MS/MS) method was developed for the determination of 3 kinds of brevetoxins(BTX) in shellfish.The samples were extracted with acetone,and purified on a C18 solid phase extraction column.The separation of the analytes was performed on an ACQUITYTM UPLC BEH C18 column with 5 mmol/L ammoumium acetate containing 0.1% formic acid-acetonitrile as mobile phase,and detected in multiple reaction monitoring(MRM) mode.The external standard method was used for quantitation.Results showed that there were good linear relationships for BTXs in the range of 1.0-100 μg/L with correlation coefficients(r2) not less than 0.996.The quantitation limits of the method were 3.0 μg/kg.The recoveries for the brevetoxins ranged from 80.0% to 87.5% with relative standard deviations of 1.3%-5.4%.The method was suitable for the determination of brevetoxins in shellfish with advantages of simple processing,high sensitivity and good stability.