Residual renal function has been proven to contribute to improved survival and quality of life of dialysis patients. It is now recognized as an important factor in the prognosis of PD.The RAAS system is involved in the development of renal diseases. Angiotensin II and aldosterone are vital in this process. The beneficial effect of angiotensin-converting enzyme inhibitor or angiotensin receptor blocker on residual renal function has been demonstrated in peritoneal dialysis patients. Unfortunately, neither ACE inhibition nor angiotensin receptor blocker fully supprsses aldosterone production. Now much focus has been placed on aldosterone antagonist.