The purpose of this study was to investigate and analyze the high frequency electrocardiogram (HFECG) for middle-aged and elderly people.138 subjects were chosen in our study.The mean age was 60.38 years.Among them,72.1 per cent were between 50 and 69 years.The results showed that (1) the differences were not significant between male and female groups in the mean number of high frequency notches (HFN).(2) For an increase in high frequency notches in the leads V1 and V2,we should consider the possibility of pathological changes of the anterior medial wall of heart,which was supplied by the dessending rami of the right anterior coronary artery,on the one hand,and it might remind us to pay great attention to posteromedian wall of heart,on the other hand.(3) Looking at all age groups in this study,we preliminarily found that the age peak of ischemic heart disease was between 50 and 70 years,according to the number of high frequency notches in the leads of HFECG.(4) The sensitivity of HFECG for diagnosing ischemic heart disease is 40 per cent higher than that of the conventional ECG.(5) In addition,nine leads were used in this examination,which not only preserved sensitivity of six leads but also could provide a localizing value for the diagnosis of heart disease.