Introduction: Myiasis is a parasitic infestation of the animal or human body, caused by dipterous fly larvae feeding on the host's necrotic or living tissues. Intestinal myiasis is usually an accidental phenomenon, which can be caused by the ingestion of fly larvae present in food or water. Case Presentation: Herein, we present a case of accidental human intestinal myiasis, caused by Lucilia illustris larva in a 45-year-old rural woman, who was admitted to the hospital with specific abdominal pain and loose stool. The stool examination of the patient revealed L. illustris larva. Following the excretion of larva, the symptoms completely resolved within a few hours, and the patient remained asymptomatic several weeks later. Conclusions:Intestinal myiasis in humans is probably an accidental myiasis, related to the ingestion of contaminated uncooked food or water containing fly larvae, especially in individuals with poor hygienic conditions. Nevertheless, this is the first reported case of intestinal myiasis due to L. illustris in Iran.