Objective To study the mutation and expression of genes of Salmonella when screened by different concentrations of quinolone and fluoroquinolones during propagation and their relation with antibiotic resistance. MethodsSalmonella strain was cultured in broth medium and screened on nutrition plate with different concentration of quinolone and fluoroquinolones. Antimicrobial susceptibility of the screened subculture was tested by broth microdilution method, mutation of genes in quinolone resistance-determining region (QRDR) was detected using polymerase chain reaction(PCR)and DNA sequencing method, and expression level of the encoding genes of multi-drug associated efflux pump AcrAB-TolC was detected by real-time qPCR. Results Antibiotic resistance level of the subcultures screened from LB plate with quinolone and fluoroquinolones inducement increased in different extents. Mutation of Asp87Tyr in gyrA in QRDR was detected from the fifth to the seventh generation of nalidixic acid screened strains. Mutation of Asp87Asn in gyrA in QRDR was detected from the fourth to the seventh generation of ciprofloxacin screened strains. No amino acid mutation was detected from gyrA in the first to the seventh generation of gatifloxacin, levofloxacin and delafloxacin screened strains. Compared to the expression level of the multi-drug efflux pump AcrAB-TolC encoding genes of the original strain, those of the screened strains had significantly (P<0.05) increased resistance. No significant difference was detected among the expression level of AcrAB-TolC encoding genes in the seventh generation of screened strains. The ratio of the minimal inhibitory concentrations (MICs) of the screened strains and that of Salmonella Typhimurium(ATCC 14028s), gene variation and relative expression level of acrAB-tolC of Salmonella significantly positive correlated with subculture generation and antibiotic concentration. Conclusion Under the selective pressure of antibiotics, Salmonella strain could adapt the stress environment through QRDR mutation and increase the expression level of multi-drug efflux pump AcrAB-TolC. When the next generation fluoroquinolone was used, the mutation frequency of QRDR decreased. After subcultured several times, the expression level of acrAB-tolC of the screened strains increased, however, no significant difference was detected among the expression level, which avoided the antibiotic resistance of Salmonella to be further increased.