The extensively drug-resistant (XDR) ST463 strains, which co-harbor plasmid-associated metallo-β-lactamase (MBL) and genes, exhibit significant resistance and virulence, posing great clinical treatment challenges. Here, we report on three XDR ST463 strains, PA64, PA3117, and PA30, all carrying two plasmid types. One plasmid was a ~450 kb IncP-2-type megaplasmid named pPA64_1, pPA3117_1, and pPA30_1 in strains PA64, PA3117, and PA30, respectively. The other plasmid was a type I plasmid named pPA64_2, pPA3117_2, and pPA30_2 in strains PA64, PA3117, and PA30, respectively, harboring the gene in the core genetic platform IS-IS. The gene copies were associated with IS-mediated inversion or duplication events. Notably, the IncP-2 megaplasmids pPA64_1, pPA3117_1, and pPA30_1 were associated with a variable ~57.3 kb Tn-like transposon named Tn, Tn, and Tn, respectively. Tn carried the MBL gene which was located in the class 1 integron In, followed by an IS-associated module and the IS-composite transposon Tn. On this basis, other IS-associated modules (IS, IS, and IS) were inserted between In derivatives and IS, resulting in a novel transposon, Tn6, carrying two MBL genes, and . In contrast to Tn6, Tn had another inserted copy of IS. We inferred that the evolution of the Tn-like transposon might be driven by the recruitment of IS-associated antimicrobial resistance (AMR) modules under antibiotic pressure in a clinical setting.