Objective proteins synthesized from genetically recombined Escherichia coli strain (E. coli) have been successfully produced by microbe fermentation, but complicated separation and purification steps always make against the maintenance of activities as well as increase the cost. Aiming at simplifying the process, an idea of administrating directly the microencapsulated genetically recombined E. coli is proposed. In this paper, study on culture of E. coli DH5α immobilized in alginate/chitosan (ACA) microcapsule is presented. It was found that E. coli DH5α grew well in the microcapsule with stable growth period longer than that of suspension culture, and cell aggregation phenomenon was observed. In vivo experiments showed that ACA microcapsules with E. coli DH5α stayed over 48 h in mouse intestine, and the morphology of microcapsules was kept intact. These preliminary results have demonstrated that administration of microencapsulated E. coli DH5α is safe, which layed the foundation for microencapsulated genetically recombined E. coli as carriers of gene engineering drugs.