The isolation rates of thermotolerant Campylobacter species in free-ranging domestic chickens and confined chickens from Iquitos city, Peru, were determined. Campylobacter spp. were isolated in 54.0% of the former group of chickens, being less frequent (35.0%) in the latter (p < 0.05). Of the classical thermotolerant species, C. jejuni and C. coli were the most frequent. However, the presence C. lari suggests that the chickens might be an important reservoir of this bacterium.