We encountered a very rare case of eosinophilic gastroenteritis accompanied with fasciitis of the extremities. The patient was a 28-year-old woman with epigastralgia, eosinophilia plus leukocytosis, massive pleural effusion and ascites, and thickening of the walls of the intestine. Increase of the eosinophilic fraction in her ascites led to a diagnosis of eosinophilic gastroenteritis. She soon developed resting pain in all limbs and MRI revealed fasciitis. Prednisolone was effective in treating both gastroenteritis and fasciitis.