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AIM: We aimed to characterize the phenotype and genotype of 17 carbapenem-resistant Klebsiella pneumoniae (CRKP) strains isolated from 2006 to 2021 in French Polynesia and to identify potential mobile genetic elements (MGEs) associated with carbapenemase genes responsible for their dissemination. BACKGROUND: CRKP strains have emerged as a significant nosocomial pathogen worldwide, representing a global health threat. METHODS: Whole-genome sequencing using Miseq and Nanopore technologies and computational analysis of 17 CRKP strains were performed. RESULTS: All strains were resistant to ertapenem (MIC 0.5→>32 mg/L), two to imipenem (MIC >32 mg/L) and ten to meropenem (MIC 4→>8mg/L). Carbapenem resistance was mediated by class B β-lactamase (five NDM-1 and two NDM-9) and/or mutations in ompk35 (n=4) and ompk36 (n=6) genes encoding two major porin membrane channels (Fig.1). Interestingly, a novel composite transposon Tn7722 (16,246 bp) of the IS6 family, was identified on five plasmids of two incompatibility types IncF, IncR in NDM-1 isolates. This transposon also contained qnrS1, aph(3’)-VI conferring resistance to fluoroquinolones and aminoglycosides. We found other genomes of bacterial species from different continents harboring a similar Tn77220-like element in NCBI database (Fig.2). NDM-9 gene was carried on two identical ∼ 260-kb conjugative plasmids of IncHI2 type in two CRKP strains belonging to two different STs (ST34, ST307) suggesting transfer of NDM-9 by conjugation. CONCLUSION: This study highlights the potential risk of dissemination of NDM producers among CRKP isolates by MGEs in French Polynesia. Continuous genome analysis is crucial for monitoring antimicrobial resistance with real-time surveillance of CRKP.