A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)combined with QuEChERS method was developed for the simultaneous qualitative and quantitative analyses of four metabolites of nitrofuran antibiotics,including semicarbazide(SEM),1-amino-hydantoin(AHD),3-amino-2-oxazolidinone(AOZ),5-morpholino-3-amino-2-oxazolidone(AMOZ).The samples were hydrolyzed with HCl,and derivatized with 2-nitrobenzaldehyde at 37 ℃ for 16 h.The derivative solutions were adjusted to pH 7.0-7.5.The analytes were extracted and pured by Bond Elut QuEChERS.The separation was carried out on a C18 column,using acetonitrile-0.1% formic acid as mobile phase by gradient elution.The analytes were detected by tandem mass spectrometry with electrospray ionization source under multiple reaction monitoring(MRM) mode.The method showed a good linearity between peak area ratios of the analytes to the internal standard and concentration of the analytes with correlation coefficients all above 0.999 over the dynamic range of 1.0-10 μg/L.The limits of detection(LODs) and quantitation (LOQs) of four antibiotics were 0.15 μg/kg and 0.5 μg/kg,respectively.The average recoveries of all the compounds at four spiked levels of 0.5,1.0,2.0,5.0 μg/kg ranged from 88.0% to 109.6% with RSDs (n=6) of 3.8%-11.0%.This method was used to detect 200 batches of holothurian in Dalian with the passing percentage of 95%.Compared to the traditional pretreatment method,this method is more easy to operate and less solvent comsuming,and is proved to be fast and effective for the simultaneous qualitative and quantitative analyses of the metabolites of nitrofuran antibiotics in holothurian.