We proposed a simple and rapid gene isolation system from Escherichia coli O157. The metal coating hollow fiber membrane was used in this system. Because the membrane was coated with metal, it could be used both as a filter and as an electrode. E coli O157 was trapped in the membrane by aspirating human feces sample with the micropump. After that, to isolate the gene from the bacterial body, which was chemically lysed, an electric field was applied to the membrane. The verotoxin type I gene of E. coli O157 could be isolated from the human feces sample, including 4x10(6) CFU/ml of E. coli O157 by above processes. In addition, concentrating the genes with an electric field enabled detection of E coli O157 from 4x10(5) CFU/ml of human feces sample. The required time for gene isolation was no more than 15 min. This system consisted of the micropump, DC power supply and the metal coating hollow fiber membrane. From these results, it was suggested that gene isolation using this membrane might be done automatically because it needed few apparatuses and processes.