A liquid chromatography-tandem mass spectrometric（LC-MS/MS） method was developed for the simultaneous determination of four nipagin esters,including methylparaben,ethylparaben,propylparaben and butylparaben in aquatic products samples（Sargassum fusiforme,porphyra,hairtail,yellow croaker）.The samples were extracted by ultraphonic extraction with methanol.Extracting solution was filtered,then cleaned up with MCX solid phase extraction.The analysis was performed on an Agilent ZOBRAX C18 column（2.1 mm×150 mm,5 μm） using a gradient elution program with mobile phase of 0.1% acetic acid and acetonitrile.The analytes were determined by an electrospray ionization tandem mass spectrometry in multiple reaction monitoring（MRM） mode,and quantified by internal standard method.The results indicated that a good separation of four compounds was obtained in 7 min.The calibration curves for four nipagin esters were linear in the range of 5.0-100.0 ng?mL-1 with correlation coefficients not less than 0.999 2,and the limits of quantitation（LOQs） were all 10.0 μg?kg-1.The average recoveries at three spiked levels ranged from 75%-96% with RSDs not more than 7.1%.This method shows the advantages of simplicity,accuracy and sensitivity,and is suitable for the analysis of four nipagin esters in aquatic product samples.