| Summary: | With the wide use of carbapenems, carbapenem-resistant <i>Enterobacterales</i> have been increasingly reported worldwide. In this study, one <i>bla</i><sub>OXA-181</sub>-positive <i>Pseudocitrobacter faecalis</i> strain was isolated from the blood culture of a patient with a bloodstream infection in China, which was its first clinical report outside Pakistan. Species identification of <i>P. faecalis</i> was initially performed using MALDI-TOF/MS and further confirmed by 16S rRNA gene and housekeeping gene sequencing. The antimicrobial susceptibility testing was determined through the broth microdilution method, and their clonal relationship was analyzed by pulsed-field gel electrophoresis. To study the transmission and genetic structure of the <i>bla</i><sub>OXA-181</sub> gene, a transformation test and whole-genome sequencing (WGS) were performed. The results of the antimicrobial susceptibility testing indicated this <i>P. faecalis</i> was resistant to carbapenems, quinolones, and commonly used β-lactam/β-lactamase inhibitor combinations. Through WGS and transformation experiments, <i>bla</i><sub>OXA-181</sub> and <i>qnrS1</i> genes causing antibiotic resistance were located on a 55,148-bp length IncX3 type plasmid with a truncated ColKp3 replicon gene. As a rare species of <i>Enterobacterales</i>, <i>P. faecalis</i> was clinically reported in China for the first time, and the <i>bla</i><sub>OXA-181</sub> gene it carried was located on a globally disseminated IncX3 plasmid. The spread of such bacteria and antibiotic resistance requires more clinical attention.
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