A total of 232 isolates of gram-negative bacteria were recovered from mammals, reptiles, and birds housed at Asa Zoological Park, Hiroshima prefecture, Japan. Forty-nine isolates (21.1%) showed multidrug resistance phenotypes and harbored at least one antimicrobial resistance gene. PCR and DNA sequencing identified class 1 and class 2 integrons and many β-lactamase-encoding genes, in addition to a novel AmpC β-lactamase gene, bla _CMY-26 . Furthermore, the plasmid-mediated quinolone resistance genes qnr and aac ( 6 ′)- Ib-cr were also identified.