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Abstract: Antimicrobial resistance caused by efflux systems is not widely studied in Staphylococcus aureus. In the present study, prevalence of NorA and NorB efflux pumps was studied in thirteen Methicillin-Resistant Staphylococcus aureus (MRSA) strains using a pair of primers with Polymerase Chain Reaction (PCR). Antibiotic susceptibility study in NorA and NorB efflux positive isolates was carried out according to the Clinical and Laboratory Standards Institute guidelines. To evaluate the effects of various drugs at half of their MIC on NorA and NorB efflux pump, expression of NorA and NorB genes was measured through semi-quantitative PCR. Our results demonstrated that out of 13 MRSA strains, 8 strains were both NorA and NorB positive and 2 strains were NorA positive. Susceptibility data revealed that Vancoplus appeared to be the most active antibacterial against NorA and NorB efflux pumps positive MRSA strains with MIC values 0.25 to 0.5 µg mL−1. The second most active antibacterial agent was teicoplanin with MIC values 0.5 to 1 µg mL−1. The MICs of vancomycin and daptomycin ranged from 32 to 64 µ