ABSTRACT Background and Objective: Lophomonas blattarum is a multi-flagellate protozoan that is commensal in hindgut of cockroaches and other insects. The protozoan can cause respiratory infection in humans. Most cases of the infections with this protozoan have been reported in China. Here, we present a case with chronic respiratory allergy caused by L. blattarum in Golestan province, Iran. Case Description: The case was a 37-year-old male with history of respiratory conditions and he was immunocompetent. An athlete. L. blattarum was detected in direct smear examination of sputum, Conclusion: Since we found respiratory infection in an immunocompetent individual who was also an athlete, it is necessary to study this parasite and its life cycle and transmission methods. It is also suggested to consider L. blattarum infection and treatment with metronidazole in cases of chronic allergies, especially those that do not respond to treatment. Keywords: Lophomonas blattarum, Respiratory Allergies, Iran.