A host-plasmid lethal balancing system was constructed based on asd gene in an avirulent strain of S.flexneri to express coli surface antigen 6 of enterotoxigenic Escherichia coli. The results of Western-blotting demonstrated that avirulant strain of S.flexneri FWL01 expressed CS6 steadily. Immunofluorescence analysis showed that S.flexneri FWL01 carrying the plasmid pZLG6 can be excited fluorescence on its surface. Antibodies against CS6 and LPS of Shigella can be detected in sera of mice immunized with recombinant bacteria either orogastrically (o.g.) or intranasally(i.n.); simultaneously sIgA against CS6 can also be detected in the intestine. This is helpful for constructing multivalent recombinant vaccine for prevention of bacterial diarrhea.