The concept of acute renal failure with anuria due to malignant nephro-angiosclerosis, is uncommon. We report two cases and compare them with others in the world literature. Knowledge of this disease entity is of triple interest: In diagnosis and classification in the field of acute vascular nephropathy with anuria. We cannot emphasise too much the interest of early renal biopsy after correction of abnormal blood pressure. In physiopathology, these malignant nephro-angioscleroses give rise to hypertension of pressor type with high renin levels. Finally therapeutic, for there exist drugs adapted to this type of hypertension. The association of acute renal failure and malignant nephro-angiosclerosis should be treated as an emergency, to avoid the passage to terminal and irreversible renal failure.