Objective To determine 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) residues released from protein bound AMOZ in animal tissues.Methods Polyclonal and monoclonal antibodies were produced in this study.A rapid,sensitive,and specific competitive direct enzyme-linked immunosorbent assay (cdELISA) was developed.Results Rabbit polyclonal antibodies were used in the optimized cdELISA method,and exhibited negligible cross-reactivity with other compounds structurally related to AMOZ.The ICso of the polyclonal antibody was 0.16 ng/mL.The method limit of detection in four different types of animal and fish tissues was less than 0.06 ug/kg.Recoveries ranged from 80％ to 120％ for fortified samples with the coefficient of variation values less than 15％.The results of the cdELISA method were in good agreement with the results from an established liquid chromatography-tandem mass spectrometry confirmatory method used for AMOZ residues.Conclusion The cdELISA method developed in the present study is a convenient practical tool for screening large numbers of animal and fish tissue samples for the the detection of released protein bound AMOZ residues.