An analytical method for the simultaneous determination of norfloxacin， ciprofloxacin and enrofloxacin residues in aquatic products by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) was established. The sample was extracted with acetonitrile, cleaned-up by hexane, and concentrated with a rotary evaporator. The mass spectrometer was operated in the positive ion mode using selected reaction monitoring for the qualitative and quantitative analysis. The detection limits of this method for norfloxacin, ciprofloxacin and enrofloxacin residues were 1.0 μg/kg, and the limits of quantification were 2.0 μg/kg. The relative standard deviations ranged from 1.8% to 10.9% (n=6) and the recovery rates were from 68.5%to 102.1%. The method was proved to have good repeatability and high sensitivity, and be rapid, reliable and suitable for the simultaneous determination of norfloxacin, ciprofloxacin and enrofloxacin residues in aquatic products.