Abstract: Objective To evaluate the changes of electrocardiogram(ECG) in the senile diabetes mellitus(DM) with hypoglycemia. Methods The ECG of the 75 cases of senile DM with hypoglycemia from June 1, 2000 to December 30, 2005 were studied retrospectively. Results The changes of ECG were found in 67 cases(89%) of all the patients. The highest morbidity of ECG abnormality was arrhythmia which was found in 54 cases(81%), coronary insufficiency in 39 cases(52%), acute myocardial infarction in 6 cases(8.00%). Conclusions The abnormalities of ECG are commonly seen in senile DM with hypoglycemia.