Background/Aims Paragonimiasis is a parasitic disease caused by Paragonimus species. Lung is the most common site, but other organs such as the central nervous system, liver, intestine, peritoneal cavity, and abdominal wall are also known to be involved. Methods A 57-year-old male was admitted for recurrent lower abdominal pain over 4 weeks. Physical examination revealed mild right lower quadrant tenderness. Laboratory findings revealed no abnormalities with normal eosinophil count. He went through computed tomography scan and there was diffuse peritoneal infiltration and subtle wall thickening of right colon with multiple reactive lymph nodes (Fig. 1A). He underwent colonoscopy and esophagogastroduodenoscopy (EGD), and no abnormal finding was found. We suspected tuberculous peritonitis and performed exploratory laparotomy. Intraoperative findings showed multiple small whitish nodules and abscess on the peritoneum. Pathologic reports confirmed that there were numerous eggs of Paragonimus westermani (Fig. 1B). ELISA was positive for antibodies against P. westermani in the serum. Retrospective history results revealed that he had consumed freshwater crabs. Results He was treated with praziquantel (25 mg/kg, 3 times daily for 3 days) and his pain was resolved after treatment. Conclusions Human infection of Paragonimus species occurs by ingestion of raw or pickled freshwater crustaceans, such as crab or crayfish with metacercariae. The metacercariae excyst in the duodenum, and then pass through the intestinal wall, peritoneal cavity, diaphragm, and pleural cavity to the lung. Due to this mi-gratory route, ectopic infections can occur such as peritoneum. The diagnosis of ectopic infection can be made when worms or eggs of characteristic shape are found on tissue. ELISA for antibodies or molecular identification by PCR can be helpful for diagnosis. [ABSTRACT FROM AUTHOR]