A case of severe hypertension and acute renal failure developing in a 56 year old woman affected by diffuse scleroderma is reported. The patient was treated by peritoneal dialysis, antihypertensive agents and plasma infusions, which led to the correction of arterial hypertension and partial recovery of renal function. This report emphasizes the possibility that the correction of malignant hypertension may prevent progressive renal falure in some patients affected by diffuse scleroderma.