Abstract: Objective To evaluate the feasibility of using gene STY3671 in detection of Samonella typhi. Methods Proteomics comparison between outer membrane proteins of S. typhi and S. paratyphi A was conducted, one of the specific dots was identified, and primers were designed according to its coding sequence, PCR test was performed by using epidemic strains of Salmonella, then the sensitivity and specificity of the assay were evaluated. Results A 807 bp PCR fragment was successfully amplified from all 184 strains of S. typhi, random sequencing of the fragments showed coincidence with gene STY3671 in strain CT-18. No fragment was amplified from any S. paratyphi A and other Salmonella strains. Conclusion STY3671 is a specific target to distinguish S. typhi from S. paratyohi A and other Salmonella, this assay has high sensitivity and specificity and might be used in diagnosis of typhoid fever.