Crohn's disease of the perineum is notably resistant to treatment. We describe our experiences of tacrolimus ointment application in three patients with intractable perianal Crohn's disease. At the time of diagnosis patients showed anal fissure with ulcer, anal fistula, or perianal abscess, respectively. These lesions did not respond to steroid, metronidazole, mesalazine, or azathioprine, though the pediatric Crohn's disease activity index was markedly improved during the treatment period (4 to 12 months). Topical tacrolimus was applied and resulted in marked healing and a rapid granulation of cavity edges within 6 weeks to 3 months. Topical tacrolimus at a low dose shows a promise for the management of childhood perianal Crohn's disease. Further controlled studies are required to assess the efficacy and safety of this treatment.