An ultra performance liquid chromatography-tandem mass spectrometric method with solid phase extraction was established for the simultaneous determination of 14 macrolide drugs in pork samples.Samples were extracted with 70%(volume fraction) acetonitrile

purified by solid phase extraction using a hydrophilic lipophilic balanced(HLB) polymer

and separated on a C18 column(100 mm×2.1 mm，1.7 μm) with acetonitrile and 01% formic acid-2 mmol/L ammonium acetate solution as mobile phases by gradient elution.The analytes were detected by mass spectrometry in positive ion mode under multiple reaction monitoring(MRM) scanning mode

and quantified by external standard method.Results showed that good linearities for 14 macrolide drugs were obtained in the corresponding mass concentration ranges with correlation coefficients(r2) larger than 0.995.The detection limits and quantitation limits of the method were in the ranges of 0.1-0.8 μg/kg and 0.5-3.0 μg/kg

respectively.Recoveries at low

medium and high spiked levels were in the range of 71.1%-102%

with relative standard deviations(RSD) less than 6.0%.This method could be applied in the analysis of macrolide drugs in pork samples with good accuracy and reliability.