OBJECTIVES: The AA report a case of a patient with acute abdomen caused by intestinal Anisakiasis, a fish-transmitted infection that results from ingestion of raw or improperly cooked fish contaminated by live larvae of Anasakis Simplex, a round worm from the order of Ascaridida. MATERIAL AND METHODS: A 33 year-old man, presented to the Emergency Room with severe upper abdominal pain, nausea and vomiting, without fever. The patient revealed that he had eaten pickled anchovies a few days before. RESULTS: On the exploratory laparotomy an edematous and stenotic tract of 15 cm of jejunum was found, and a segmental resection was performed. Histologically, the resected jejunum showed a conspicuous and diffuse inflammatory infiltration, predominantly made up of eosinophil granulocytes, numerous mucosal erosions and the presence in the submucosa of sections of parasites which were identified as Anisakis Simplex larvae. DISCUSSION: The ingestion of fish contaminated by Anisakis larve is often followed by the appearance of systemic or gastrointestinal symptoms due respectively to the direct larve localization and the allergic reaction to some parassite components. Diagnosis is made frequently difficult by clinical manifestations that could mime symptoms of other diseases more common in Italy. CONCLUSIONS: Globalization has made Anisakiasis a more and more frequent disease worldwide, as increased mixture of different cultures and international travelling has allowed the spreading of risky feeding habits. That’s why Anisakiasis should be considered in differential diagnosis of intestinal obstruction in patients with positive anamnesis for suspiciously cooked or conserved seafood eating.