Prevalence of diabetic nephropathy after 20 years of type 1 diabetes duration amounts for 30 - 40 %. We found in type 2 diabetic patients the prevalence of microalbuminuria 23 % and clinical proteinuria 11 %. Early screening of microalbuminuria (30 - 300 mg/24 h), the first manifestation of diabetic kidney damage, is an important tool in the prevention of diabetic nephropathy. Optimal glycaemic control is effective mainly in incipient and overt nephropathy without severe reduction in glomerular filtration rate. The goal of antihypertensive therapy is to decrease blood pressure below 130/80 mmHg. In the treatment of diabetic nephropathy with microalbuminuria or clinical albuminuria, angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) should be used, with the exception of pregnant diabetic patient or drug intolerance.