A 23-year-old woman presented with recurrence of lupus cystitis, which had been in remission under daily administration of a single corticosteroid over a period of 8 years. She was treated with increased doses of corticosteroid and immunosuppressants, i.e., cyclosporin, cyclophosphamide, azathioprine, and salazosulfapyridine, but the cystitis remained active. Since her condition became critical by the complication of intestinal pseudo-obstruction, tacrolimus was administered. This agent induced a remission promptly without significant adverse events in this patient, suggesting an efficacy to lupus cystitis refractory to corticosteroid and other immunosuppressants.