Objective To study the cause of occurrence and development in senile DN,to provide ready and effective ways of treatment and precaution.Methods Case history information of DN and NDN patients over 60 years was selected randomly;The questionnaiere was given to the patients;Their blood pressure,blood sugar,blood-fat,urinary albumin and renal function were monitored and conducted comparative analysis.Results There was a long course of disease,bad control of blood sugar,higher than 10mmol/L exceeding 2 5years and accompanying disorder of blood-fat and then gradual renal insufficiency and other multi-complication in senile DN patients.Conclusion Longtime hyperlycemia,hyperlipemia were important risk factors.Micro-albumin urinary indicates different degree of damage of kidney.Good control of blood sugar can decrease and delay occurrence and development of senile DN.