Chronic kidney disease is a worldwide public health problem because it is an important risk factor for cardiovascular disease and premature death. The metabolic syndrome, which is characterized by abdominal obesity, high blood pressure, impaired glucose tolerance, and dyslipidemia, is also an increasingly common disorder and a major risk factor for diabetes and cardiovascular disease. A close association has been found between the metabolic syndrome and the risk for developing renal impairment, clinically expressed in the form of microalbuminuria or chronic kidney disease. Several potential mechanisms, including insulin resistance, renal atherosclerosis, and inflammation, induce the deterioration of renal function. Despite the close association between the metabolic syndrome and renal impairment, it is still unclear whether and to what extent treating the metabolic syndrome will prevent renal impairment. A clinical trial is needed to clarify whether the effect of preventing and treating metabolic syndrome components will result in improved renal prognosis.