CTX-M-type extended-spectrum β-lactamases (ESBLs) are believed to spread only in Enterobacteriaceae. The acquired β-lactamases important in Pseudomonas aeruginosa include class B metallo-β-lactamases (mostly IMP, VIM, and SPM-1 types) and class A ESBLs (VEB-, PER-, GES-type). However, a single CTX-M-1-producing P. aeruginosa isolate has been reported from The Netherlands, as well as CTX-M-2- and CTX-M-43-positive P. aeruginosa isolates in Bolivia. This study reports the identification of a CTX-M-2-producing P. aeruginosa strain isolated from a Brazilian teaching hospital. During June 2005, a 63-year-old male patient with a recent hospitalization history was admitted to the intensive care unit for suspicion of pneumonia, received ceftriaxone and clindamycin, presented with septic shock four days later and died; a blood culture grew P. aeruginosa (isolate P6208). Isolate P6208 was resistant to all β-lactams tested except imipenem and ceftazidime, with ESBL production evidenced by double-disk synergy test only under unusual conditions (distance between disks of 1.5 cm center to center). It was also resistant to fluoroquinolones, amikacin, gentamicin, and tobramycin, and susceptible to colistin. The MICs of imipenem, ceftazidime, cefepime, and cefotaxime were 1 μg/ml, 2 μg/ml, 256 μg/ml, and 32 μg/ml, respectively. Cloning and sequencing of the DNA insert from isolate P6208 identified a blaCTX-M-2 gene, which was preceded by an ISCR1 element located 498-bp upstream and followed by the qacE1 gene cassette. Plasmid extraction did not evidence any plasmid, and repetitive attempts to transfer the blaCTX-M-2 gene by electroporation failed, suggesting the gene might be chromosomally located. This study identified a CTX-M-2-producing P. aeruginosa in Brazil. This finding is important since clinical laboratories may misidentify CTX-type enzymes in those nonfermenters, jeopardizing the choice of antimicrobial chemotherapy and the implementation of infection control measures. This report underlines that P. aeruginosa may become a hidden location for blaCTX-M genes.