Abstract: First we screen the Escherichia coli O157∶H7 from the fecal samples of the diarrhea patients with rapid immuno-gold-detection card. Then, we concentratetae bacterium with immuno-magnetic-bead for isolation and characterization. We find that the rapid immuno-gold-detection card can detect 70 bacterium cells per card. Escherichia coli O157∶H7 (31/34) can be isolated from 91.18% of the strong-positive fecal samples, and Escherichia coli O157∶H7 (7/128) can be isolated from 5.47% of the weak-positive fecal samples. Yet,no pathogen-ic bacteria have been isolated from those negative fecal samples. Therefore,the E.coli O157:H7 rapid immuno - gold - detection card is an advanced technique with rapidity,sensitivity and convenience. It can be applied to the eatlier aiagnose of the suspected cases and the pre - screen of fecal samples. It reduces the work hours and deserves to be popularized.