Background and Aim: The presence of qnr plasmid genes in the Enterobacteriaceae family is a major cause of quinolone resistance. Due to the increased fluoroquinolones resistance due to the prevalence of plasmid genes, the aim of this study was to determine the frequency of plasmid genes (qnrA, qnrB, qnrS, qnrC, aac (6 \\\') - Ib-cr) which are present in poultry salmonella. Material and Methods: 50 specimens were collected from bacteriological collections of Ferdowsi University of Mashhad, Faculty of Veterinary Medicine. These samples were first tested for antibi gram suseptibility and then all of them for presence of genes (qnrA, qnrB, qnrS, qnrC, aac (6 \\\') - Ib-cr) using PCR. Results: In this study, the highest resistance to nalidixic acid was observed in 16% of samples and then to 14% of flomcquin. 2% of isolates had intermediate resistance to flomcquin and 4% to Enrofloxacin. PCR tests were performed, no strains showing the presence of genes (qnrA, qnrB, qnrS, qnrC, aac (6 \\\') - Ib-cr). Conclusion: The conclusion of this study suggest that the rate of antibiotic resistance of Salmonella to quinolones by plasmid (qnr) genes is not very common in the studied poultry. But there is some antibiotic resistance that may be due to the other mechanisms, including mutations, are involved in resistance formation. Using proper antibiotic administration, it could be to treat salmonella infections and to prevent the spread of resistance by bacteria in the future.

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