This work was done to study the various bacterial species causing intestinal disturbances in infants inSharkia governorate with further assessment and iden-tification of the causative organisms :1- The study included 150 diarrhoeal cases, their ages varied between two months up to five years.2- Rectal swabs of stools werecaLly and then cui tured onmedia. examined microscopi-simple and selective3- Pathogenic organisms were isolated from 78 cases constituting (52%) total isolation rate.Escherichia coli was isolated from 30cases (38.46%) salmonella was isolated from 17 cases (21.79%)shigella from 8 cases (10.25%), Staphylococcus aureusfrom 7 cases (8.97,,/0), proteus from 7 cases (8.57%) andklebsiella from 9 cases (11.63%).4- Using agglutinating antisera polyvalent 1 andpolyvalent 11 for typable isolated E. coli strains.Also salmonella isolates were subjected to sero- logical identification by using slide agglutination technique.