The occurrence of intestinal Behçet's disease is not common so that misdiagnosis with inappropriate treatment often results in death. Due to this circumstance intestinal Behçet's disease is noted as a very serious complication of Behçet's disease. The identity of intestinal Behçet's disease and its patient manifestation remain obceure. As members of the national project team for intestinal Behçet's disease, we surveyed the state of intestinal Behçet's disease in Hokkaido. The results are summarized as follows: 1) The occurrence in Hokkaido of intestinal Behçet's disease is higher than the national average in concordance with a high rate of Behçet's disease itself. 2) Intestinal Behçet's disease, incomplete type, was observed to be more frequent in the female which differs from the other complications of Behçet's disease. 3) Ulcers which develop in the ileus are apt to perforate (85.7%) giving rise to frequent emergency operations. On the other hand, ulcers in the ascending colon are not as liable to the perforate (25.0%). 4) Ulcers which develop in the ileum are often round with the part under the surface being quite deep and large. Ulcers in the ascending colon are usually of various shapes and are not very deep. 5) Through a retrospective review of the cases of Behçet's disease, the probability of an ulcer occurring or not is difficult to predict at this time.