A 53-year-old woman presented with oliguria, urinary frequency, abdominal pain and severe edema of the lower extremities. Her serum creatinine was 8.1 mg/dl. Computed tomographic and ultrasonographic studies showed a severely dilated urinary bladder, and bilateral hydroureteronephrosis. Examination of a urinary bladder biopsy specimen showed subepithelial edema and infiltration by lymphocytes and plasmacytes. However, the patient complainted of dry mouth and dry eyes. Ophthalmologically, the Schirmer test was positive. A biopsy of the minor salivary glands in the lip showed chronic sialoadenitis. A diagnosis of Sjögren's syndrome complicated by interstitial cystitis was made. Since she had been anuric, secondary to urinary obstruction, intermittent self-catheterization was started. Combination of corticosteroid and cyclosporin therapy was initiated. Spontaneous urination began, and gradually the patient's symptoms remitted. After 8 months of therapy, bladder capacity increased from 140 ml to 350 ml, and she voided approximately 1,200 ml by herself and 600 ml by catheterization daily. This case suggests that when severe interstitial cystitis is associated with Sjögren's syndrome, a therapeutic trial of corticosteroids and cyclosporin may be beneficial.