The clones of phage antibody (PhAb)to E．Coli J5 strain were enriched and screened by panning and filter blot with E．Coli J5 strain from a human antibody library. Four positive clones binding to E．Coli J5 strain were determined by ELISA. The results of inhibition test showed that the binding of positive clones to antigens could be respectively inhibited by E．Coli J5 strain, E．Coli Rc-LPS and anti-CGL MAbs to E．Coli J5 strain. PCR amplification showed that all of the four positive clones contained the expected heavy and light chain genes of human Fab fragment. SDS-PAGE and Western blot analysis confirmed that positive clones were able to express about 50 ku proteins after induced with IPTG.These data indicate that four positive clones express the human Fab fragment with antigen specificities.