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Carbapenem-resistant <i>Acinetobacter baumannii</i> (CRAB) isolates of global clone 1 (GC1) and global clone 2 (GC2) have been widely reported. Nevertheless, non-GC1 and non-GC2 CRAB strains have been studied less. In particular, no reports concerning sequence type 46 (ST46_Pas) CRAB strains have been described thus far. In this work, the genomic features and possible evolution mechanism of ST46_Pas OXA-23-producing CRAB isolates from clinical specimens are reported for the first time. Antimicrobial susceptibility testing of three ST46_Pas strains revealed identical resistance profiles (resistance to imipenem, meropenem, ciprofloxacin and the combination of cefoperazone/sulbactam at a 2:1 ratio). They were found to belong to ST46_Pas and ST462_Oxf with capsular polysaccharide 28 (KL28) and lipooligosaccharide 1 (OCL1), respectively. Whole-genome sequencing (WGS) revealed that all contained one copy of chromosomal <i>bla</i>_OXA-23, which was located in a novel IS<i>Aba1</i>-based Tn<i>7534</i> composite transposon. In particular, another copy of the Tn<i>7534</i> composite transposon was identified in an Hgz_103-type plasmid with 9 bp target site duplications (TSDs, ACAACATGC) in the <i>A. baumannii</i> ZHOU strain. As the strains originated from two neighboring intensive care units (ICUs), ST46_Pas OXA-23-producing CRAB strains may have evolved via transposition events or a p<i>dif</i> module. Based on the GenBank database, ST46_Pas strains were collected from various sources; however, most were collected in Hangzhou (China) from 2014 to 2021. Pan-genome analysis revealed 3276 core genes, 0 soft-core genes, 768 shell genes and 443 cloud genes shared among all ST46_Pas strains. In conclusion, the emergence of ST46_Pas CRAB strains might present a new threat to healthcare settings; therefore, effective surveillance is required to prevent further dissemination.