BACKGROUND: Campylobacteriosis is one of the most commonbacterial intestinal disorders of humans in many countries.A wide range of domestic and wild bird species have been identifiedas natural reservoirs. OBJECTIVES: The aim of this studywas to determine the Campylobacter spp from pet birds andscreen the determined Campylobacters for presence of virulencecytolethal distending toxin (cdt) genes. METHODS: A totalof 660 fecal samples from 32 different species of pet birds weretaken and examined for detection of Campylobacter spp. andwere investigated for presence of cdt genes. All the sampleswere collected from clinically healthy birds that were kept incage, zoological parks, and/ or in zoo of Tehran, the capital ofIran. RESULTS: In total, 20 thermophilic Campylobacter weredetected from 8 different avian species. From 20 confirmedCampylobacter spp., 16 samples (80%) were C. jejuni positiveand 4 (20%) were C. coli in species-specific PCR test. Furthermore,out of 20 detected Campylobacter, 13 (65%) harboredthe various subunits of cdtA, cdtB and cdtC genes, and 7 (35%)were negative for all tested cdt genes. CONCLUSIONS: Our findingsindicate that the carriage rate of Campylobacter in differentspecies of cage and/or in zoo birds is high and confirm thatcdt genes may frequently be present in campylobacter spp.