An infestation of Ornithostrongylus quadriradiatus, has been found in a racing pigeon Columba livia domestica). In addition, this individual had a mild infection with Trichomonas spp. and Eimeria spp. The bird showed symptoms of increased appetite; unformed, dark- green feces; and lack of typical male behavior, but the general condition of this pigeon was good. The pigeon was euthanized because of a permanent inability to fly due to an injury to the wing. A postmortem examination revealed the presence of very small dark-pink twisted nematodes with the morphology of O. quadriradiatus in the small intestine, mainly the duodenum. Histopathology showed segmental inflammatory changes in the intestines caused by both blood-sucking nematodes and Eimeria spp. The 5.8S ribosomal ribonucleic acid polymerase chain reaction amplicons from deoxyribonucleic acid extracted from O. quadriradiatus had 82.40% identity with Australostrongylus victoriensis and 81.20% with Travassostrongylus spp. This is the first molecular characterization of O. quadriradiatus—a relatively rare pigeon parasite.