Abstract: A highly sensitive detection of 10 nitroimidazole drug residues in aquatic products has been achieved by optimizing the sample pretreatment methods combined with high performance liquid chromatography-tandem mass spectrometry(HPLC-MS).The nitroimidazole drug residues in samples were extracted with ethyl acetate and removed fat by n-hexane, then quantified by the external standard method after detected in the positive ion mode by high performance liquid chromatography-tandem mass spectrometry.Under the optimized pretreatment methods and instrument conditions, the calibration curves were linear in a concentrations range of 5.00~200 μg/mL with R>0.995 0.The average recovery was 70.2%~119% and the relative standard deviation was in the range of 1.46%~13.5% for spiked aquatic sample with 1.00 μg/kg, 2.00 μg/kg and 5.00 μg/kg of nitroimidazoles.The accuracy and precision of the method was in accordance with the requirements of veterinary drug residue detection, and the operation was simple and fast.It showed that the method was suitable for the nitroimidazole drug residues detection of large quantities of samples.