Only a few cases of Acanthocephala infections have been reported in humans, and Moniliformis moniliformis is the most common species around the world. We report here a case of infection with M. moniliformis, which passed in the stool of a 2-year-old girl in Iran. The patient had abdominal pain, diarrhea, vomiting, and facial edema. According to her mother, the patient had habit of eating dirt and once a cockroach was discovered in her mouth. In stool examination, eggs of M. moniliformis were not found. She was treated with levamisole and the clinical symptoms reduced within 2 weeks. The specimen contained 2 pieces of a female worm with a total length of 148 mm lacking the posterior end. The spiral musculature of the proboscis receptacle and the shape of the trunk allowed its generic determination. Previously 2 cases of M. moniliformis infection were reported in Iran. This is the 3rd case of M. moniliformis infection in Iran.