A new magnetic affinity immunoassay（MAIA） method based on gold-magnetic particle and HRP-conjugated phage antibody was developed.Gold-magnetic particle were coated with staphylococcus protein A（SPA） and coupled with polyclonal antibody（pcAb） to construct functionalized capturing probes,and HRP-conjugated phage antibody was then used as specific detecting probe to design MAIA for trace detection of abrin.The calibration curve was linear（r=0.991 0） in the range of 0.008-250 μg/L,with a limit of detection（LOD） of 0.008 μg/L,and a limit of quantitation（LOQ） of 0.008 μg/L.Integrating the unique advantages of functionalized SPA gold-magnetic particle probe and HRP-conjugated phage antibody with its high sensitivity,specificity and anti-interference,the method is proven to be well suited for the analysis of trace abrin in various environmental samples.