Abstract: In this study, a pair of specificity primers designed basis on the Salmonella’s inv A genome sequence, then ,the tests of the specificity and sensitivity of Salmonella and the optimal conditions of PCR (optimal anneal temperature, optimal concentration of templates, etc.) had been discussed . The results showed that the specificity of this method to detect Salmonella is 100% and the limit of detection is 1.43CFU/l0g/ sample, the best anneal temperature of the PCR test is 65℃, the best template concentration is between 104～108copies/ml. The result of the experiments demonstrated that the PCR assay is a rapid, simple, economic and more specific, sensitive to traditional culture for the detection of Salmonella in the food samples, and available for screening of Salmonella in a large number of food samples.

Key words: PCR detection, Salmonella, template, primers, specificity