The first known case involving an association of Sweet's syndrome with Crohn's disease is described. A 36-year-old woman developed a diarrhea, fever, and infiltrated erythematous cutaneous plaques on neck and limbs, consistent with a presumptive diagnosis of Sweet's syndrome. This was confirmed by a skin biopsy showing a dense dermal infiltrate of polymorphonuclear leukocytes. Crohn's disease, extending from the anus to the terminal ileum, was diagnosed as well. Prednisolone treatment resulted in the improvement of both the bowel disease and skin lesions.