The present study was undertaken to define the role of the flagella proteins, baetrine and lipopolysaccharides (LPs) of Salmonella enterica serovar Typhimurium in the induction of protective immunity against a challenge with homologous S.Typhimurium and heterologous. S. Typhi. Flagellae bactrine, and LPs.of S. typhimurium were extracted and characterized using. Immunoblotting analysis , In the active immunization assay, flagellae or bactrine 50ug conferred 100% protection to mice challenged with up to 500 LDS5O of S. Typhimurm. Even at 90 days post-immunization a subsantial level of protection (78%) was observed in me immunized mice, while bactrine was capable inducing long lasting protection (100%). immUnization with LPs 50 ug was considerably inferior to the flagellae or bactrine in the induction short duration immune status. The results indicated that flagellae, probably bactrine are valuable immunogenes in the protection against Salmonella infection. In addition, cross- protection against two Salmonella species can be obtained. Flagellae of salmonella typhimurium, was found to be a suitable antigen for eliciting delayed-type hypersensitivity in mouse salmonellosis.