A liquid chromatography-tandem mass spectrometric(LC-MS/MS)method was developed for the determination of gossypol in feed.The sample was extracted with acetone-water(7∶3).The compound was separated on a C18 column(100 mm×2.1 mm,3.5 μm)with acetonitrile – 0.1% formic acid as mobile phase by gradient elution.The detection of gossypol was carried out by LC-MS/MS with positive electrospray ionization under the multiple reaction monitoring mode and quantified the external standard method.The limits of quantitation(S/N＞10)was 1 mg/kg.Under the optimal conditions,the calibration curve was linear in the range of 10-100 μg/L with correlation coefficient of 0.993.The recoveries of gossypol at the spiked levels of 1,20,40 mg/kg in feed ranged from 83.8% to 97.5% with relative standard deviations(RSDs)of 1.3%-5.2%.With the advantages of easy operation,higher recoveries and good precision,the method was suitable for the confirmation and quantification of gossypol residue in feed.