Sclerosing peritonitis (SCP) is a rare complication of peritoneal dialysis. Most of the patients with this serious complication have been treated in a symptomatic and conservative manner. Other patients have undergone risky surgical interventions. Recently it was reported that immunosuppressive therapy after renal transplantation was effective for this complication. A 56-year-old man developed sclerosing peritonitis 5 months after switching from peritoneal dialysis to hemodialysis because of ultrafiltration failure. The patient had ongoing inflammatory signs and symptoms, and corticosteroid therapy was commenced. His condition was dramatically improved within 1 week, and he is now well on an outpatient basis with the maintenance dosage of corticosteroid. This is the first report of a patient with peritoneal dialysis-related SCP who responded favorably to corticosteroid therapy alone.