The spread of multidrug-resistant (MDR) Klebsiella pneumoniae, especially carbapenems and aminoglycosides, is a global public health challenge. Studying the genetic relatedness of bacteria from various sources, such as humans, animals, food, and the environment, can help identify potential routes of transmission and the extent of dissemination. In this study, we examined the phenotypes and genetic features of MDR K. pneumoniae isolates. Seventy K. pneumoniae strains were selected from different sources (clinics (n=55), environmental (n=7), and animals (n=8)), 43 of which were identified as carrying the blaKPC resistance gene, with a subset featuring both blaKPC-2 and blaKPC-3 variants, with different susceptibility profiles to aminoglycosides, and whole genome sequencing was used for phylogenetic analyses. Among them, 84% (n=59/70) and 53% (n=37/70) were resistant to amikacin and gentamicin, respectively. In addition, 93% (n=65/70) of the isolates harbored resistance genes, such as aminoglycoside-modifying enzymes (AMEs) and different plasmid types. Phylogenetic tree analyses showed two main clusters (A and B), and the multilocus sequence type (ST) 11 was the most frequently found among Brazilian isolates. Our findings showed a heterogeneous distribution of STs profiles in the two clusters, and a close relationship between human and animal or environmental K. pneumoniae strains.