Objective To establish a method for simultaneous determination of 8 qunolone residues ( enrofloxacin, danofloxacin, ciprofloxacin, norfloxacin, pelfoxacin, sarafloxacin, difloxacin, ofloxacin) in fish meat by high performance liquid chromatography-tandem mass spectrometry ( LC MS/MS). Methods Deuteriuru substituted reagents used as internal standards were added to fish meat samples before extraction. Samples were extracted with acidified acetonitrile, cleaned-up by hexane, and concentrated with a rotary evaporator. The mass spectrometer was operated in the positive ion mode using multiple reaction monitoring ( MRM). Results The average recoveries of 8 qunolone compounds added at l. 0 and 3. 0 lig/kg were in the range of 88. 4% -114. 9% . The detec:tion limits of compounds with the method were ranged from 0. 03 t0 0. 1 pL~kg. Conclusion The method is suitable for quantitative and qualitative detection of quinolone residues in fish samples, with advantages of quick, siruple and repeatable.