To investigate the antimicrobial susceptibility and the pulse field gel electrophoresis (PFGE) patterns of 110 Escherichia coli O157 isolates from food in China,and to complete the characteristics of Escherichia coli O157 in food for the risk assessment.MethodsAntimicrobial susceptibility of all confirmed Escherichia coli O157 isolates was determined by agar dilution method. DNA collected fromall strains was digested by Xba I according to the standard PFGE protocolof US CDC. The PFGE patterns were analyzed with BioNumerics software.ResultsOut of all the isolates, 43 strains were resistant to at least one antibiotic.The top three antibiotics were tetracycline (30.0%, 33/110) , sulfamethoxazole (29.1%, 32/ 110) , nalidixic acid (26.4%, 29/ 110). In total, 24 antimicrobial resistance profiles were identified. 34 isolates were resistant to more than two antibiotics and 32 resistant to more than three antibiotics. The dominant multidrug resistant profiles were SMX (6) , AMP-NAL-SMX-SXT-TET (6) , AMP-CHL-NAL-SMX-SXT-TET(4) /AMP-SMX-SXT-TET (4) /TET (4). The antibiotic resistance rate of E.coli O157 was significantly higher than E.coli O157∶H7 (χ²=72.010 P<0.05). 37 E.coli O157∶H7 isolates haboring shiga toxin genes only were resistant to sulfamethoxazole (2.7%, 1/37), nalidixicacid (2.7%, 1/37) with no multi-drug resistant strains. Comparedby different food types, strains from raw pork and raw poultry had relatively higher resistance rates than other types of food. PFGE molecular typing completely separated E.coli O157∶hund and E.coli O157∶H7 strains.ConclusionThe antimicrobial resistance of Escherichia coli O157 isolated from food in Chinawas serious.The antimicrobial susceptibility surveillance should be strengthened, especially for E.coli O157 (including STEC E.coli O157) isolates to explore the relationship and transmission of antibiotic resistance strains between farming areas and retail sectors and to provide a scientific basis to develop antibiotic medication in farming.