Campylobacter jejuni was isolated from 44 of 313 free-living birds from Japan. The highest isolation rate was found in 30 of 87 (34%) crows (Corvus levaillanti and Corvus corone), followed by 2 of 10 (20%) blue magpies (Cyanopica cyanus), 5 of 35 (14%) gray starlings (Sturnus cineraceus), 2 of 16 (13%) domestic pigeons (Columba livia domestica), 4 of 36 (11%) bulbuls (Hypsipetes amaurotis), and 1 of 62 (2%) eastern turtledoves (Streptopelia orientalis). One-fourth of the contents of the crop and stomach of the crows was human refuse. One-third of the crop and stomach contents of gray starlings and blue magpies consisted of insects. More than one-half of the contents of bulbuls and eastern turtledoves were seeds and plant material. These differences in food habits may be a primary factor in the varying prevalence of C. jejuni in these respective avian species.