A high performance liquid chromatography-tandem mass spectrometric（HPLC-MS/MS） method was developed for the rapid determination of metronidazole（MNZ），metronidazole-OH（MNZOH）,dimetridazole（DMZ），hydroxydimetridazole（HMMNI）,ronidazole（RNZ）,ipronidazole（IPZ）,ipronidazole-OH（IPZOH） residues in feed.The samples were extracted with 0.1 mol/L pH 8.0 phosphate buffer and ethyl acetate-acetone（70∶30，by volume），then cleaned up with matrix solid phase dispersant primary secondary amine（PSA）.The extracts were defatted with hexane and cleaned up by liquid-liquid partition.The target compounds were detected by electrospray ionization（ESI） in positive mode using multiple reaction monitoring,and quantified by the isotope internal standard method.No solid phase extract（SPE） procedure was adopted，which made sample preparation simple and efficient.The calibration curves for seven target compounds were linear in the range of 2.0-100.0 μg/L with correlation coefficients more than 0.99.Average recoveries at spiked levels of 5.0-25.0 μg/kg were between 72.4% and 95.6%，with relative standard deviation less than 12.5%.The limits of detection（LOD） were 2.5 μg/kg，and the limits of quantitation（LOQ） were 5.0 μg/kg.