A case of ileus caused by intestinal anisakiasis is described in this paper. The intestine manifested a typical allergic inflamation. Pathological changes such as extensive edema 2nd fibrosis were found in the intestine. Eosinophiles, neutrophiles and monocytes also infiltrated near the site of the penetrating worm. The worm from the intestine of the patient was identified with a SEM. On the basis of the available evidence, it can be safely said that this worm is Anisakis type I larva, although the mucro on the tip of larval tail was not clear. The patient may have been infected with Anisakis larva by eating "SASHIMI" of a small yellowtail (HAMACHI) from the Seto Inland Sea, because these small yellowtail were fed fish caught near Hokkaido, Tohoku and San-in.