Abstract: Objective To investigate the relationship between the characteristics of ECG and the clinical prognosis in elderly patients with acute pulmonary embolism. Methods Eighty-three elderly patients with acute pulmonary embolism admitted in Rui'an People's Hospital were selected from April 2016 to May 2017. Abnormal ECG within 48 h and survival situation within 30 days of onset were observed. The impacts of different factors on the overall survival rate were analyzed. Kaplan Meier method was used to draw survival curve, and Cox proportional risk model was used to evaluate the influencing factors of prognosis. Results Among the elderly patients with acute pulmonary embolism, 10 were normal ECG, 73 were abnormal ECG, the abnormal rate was 87.95%. Thirty days after the onset of the disease, 48 elderly patients survived, with a total survival rate(OS) of 57.83%. The results of single factor analysis shown that there was a correlation between OS within 30 days in elderly patients with acute pulmonary embolism and coma, shock, history of heart disease, chronic lung disease, heart rate>100 times/min, clockwise rotation, complete right bundle branch block, atrial fibrillation and limb lead low voltage(all P<0.05). The Cox regression analysis showed that heart rate>100 times/min, complete right bundle branch block, shock and history of heart were independent factors influencing the clinical prognosis of elderly patients with acute pulmonary embolism. Conclusion The abnormal rate of ECG in the elderly patients with acute pulmonary embolism is very high. The abnormal rate of ECG is closely related to the clinical prognosis, and the heart rate>100 times/min, complete right bundle branch block, shock and history of heart are the independent factors influencing the poor prognosis of the elderly patients with acute pulmonary embolism.