Abstract: The incidence of chronic kidney disease(CKD) is rising yearly. It progresses to an end stage often complicated by a variety of metabolic disorders. Protein energy wasting(PEW) is a common complication of CKD patients, especially elders and CKD patients on hemodialysis. Due to a loss of fat and muscle, renal failure accelerates and there are greater risks of complications and mortality. The pathogenesis of PEW is so complex so that core link involves protein synthesis and catabolism imbalance. Besides a lower appetite, insufficient protein/energy intake, high metabolic states caused by insulin resistance, inflammation, endocrine hormones and metabolic acidosis all contribute to protein degradation. In addition, reduced exercise and insulin-like growth factor-1(IGF-1) can also lead to a decline in protein synthesis and PEW seriously affects patient's quality-of-life and long-term prognosis. Therefore early intervention and improvement of malnutrition status are vital for CKD patients.