Renal function is closely associated with the risk of mortality，cardiovascular events，and progression to end stage of renal disease for patients with chronic kidney disease (CKD).Equations for estimated glomerular filtration rate (GFR) based on serum creatinine or Cystatin C are frequently used in clinical evaluation of renal function.Although renal function can be more accurately assessed due to improvement in equations for estimated GFR,it is difficult to overcome the inherent defect of creatinine based GFR estimation.Abundant，evidence showed that Cystatin C based GFR estimation presented higher accuracy of prognosis assessment in CKD patients than creatinine based GFR estimation,thus reduce the unnecessary nephrologist referral and measurements for low risk patients,and also guarantee the timely recognization and intervention for high risk patients.This article deeply reviewed the role of serum creatinine or Cystatin C played in CKD diagnosis and prognosis assessment.（Chin J Lab Med,2014,37: 415-419）