Objectives: Plasmid mediated quinolone resistance (PMQR) genes are increasingly detected worldwide. However, in Morocco a few studies have been carried out. The aim of this study was to investigate the prevalence of these determinants among Escherichia coli and Klebsiella spp. isolated from North-West of Morocco. Methods: The prevalence of PMQR genes was investigated among 398 E. coli and 118 Klebsiella spp. clinical isolates collected between 2012 and 2015 from North-West of Morocco. Antimicrobial susceptibility was determined by disc diffusion assay and minimal inhibitory concentrations (MIC) of quinolone were determined by micro-dilution. The screening of qnrA, qnrB, qnrC qnrS, Aac(6')-Ib and qepA genes were done by PCR, DNA sequencing and RFLP analyses. Results: Among 398 E. coli and 118 Klebsiella spp. analyzed, 51% of E. coli and 61% of Klebsiella spp. were multidrug resistant (MDR). For the E. coli group, qnrB, qnrS, and aac(6')-Ib-cr genes were detected in 05.02%, 01.50%, and 13.81%, respectively. These determinants were more prevalent in Klebsiella spp. group, hence they represented 11.86%, 05.93% and 18.64% respectively. QnrA, qnrC and qepA were absent in this study. For aac(6') Ib determinant, 84.41% were belong to the Aac(6') Ib-cr variant while for qnrB and qnrS the most determined variants were qnrB1, B6, B16, B42, B66 and qnrS1, S4, S7. Different plasmid sizes were detected in PMQR strains. Conclusion: This is the first study conducted in North-West of Morocco and shows important dissemination of MDR and PMQR among Enterobacteriaceae. (C) 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.