Three cases of myelodysplastic syndrome (MDS) complicated with inflammatory intestinal ulcers all had cytogenetic abnormalities with trisomy 8. The first two patients were diagnosed with intestinal Behçets disease and were successfully treated with salazosulphapiridine, and the third patient died after leukemic transformation. We review the reported cases of MDS complicated with Behçets disease. Most of these cases are Japanese, having intestinal involvement as well as cytogenetic abnormalities with trisomy 8. We discuss the significance of trisomy 8 in intestinal involvement in MDS.