Objective To study the effects of the kind and concentration of antibiotics in pre-enrichment for the detection of Shiga toxin-producing Escherichia coli （STEC） in the current international standard method.Methods The minimal inhibitory concentrations （MICs） of three antimicrobials supplemented in an STEC enrichment broth of four official methods were measured through testing of a panel of STEC and non-STEC isolates.Results There were differences among different antibiotics for the inhibition of STEC. At the recommended concentration， acriflavine and cefsulodin inhibited the growth of stx1a and stx2b subtypes of STEC， while novobiocin inhibited the growth of stx1a， stx1c， stx1d， stx2b， stx2d， stx2e， stx2f and stx2g subtypes of STEC. In addition， there was no significant difference among MICs of STEC and other gram-negative bacteria to acriflavine， cefsulodin and novobiocin （P>0.05）. MICs of gram-positive strains to three tested antimicrobials were significantly lower than those of gram-negative bacteria （P<0.01）.Conclusion The data provided valuable evidence for the STEC enrichment method development and improvement.