We have recently encountered a case of schwannoma of the mesenterium. A 22-year-old woman was admitted with the complaint of an abdominal mass. Ultrasonography and CT scan and CT scan showed a solid mass measuring 10×7cm. Superior mesenterial angiography revealed that the tumor was fed by the jejunal arteries and stained in late phase. It was diagnosed as a solid tumor of the mesenterium of the small intestine. At laparotomy, the tumor was found to be a benign schwannoma of the mesenterium and tumor excision was performed. Histologically, the greater part of the tumor showed Antoni type A, but some part showed Antoni type B. The benign schwannoma of the mesenterium is a rare disease and in Japan only 4 reports have been available including this case. Age, sex, symptoms, diagnosis and treatment were discussed.