〔Abstract〕 Objective To explore the clinical significance of ECG in the diagnosis of atypical myocardial infarction. Methods 65 patients with atypical myocardial infarction treated in Nanyang Second People's Hospital from January 2019 to December 2020 were included as the observation group and 65 patients with typical myocardial infarction treated in the same period as the control group. ECG was performed. The first symptoms (painless, atypical pain, typical chest back + upper abdominal pain) of the two groups were compared. Coronary angiography was the gold standard, the diagnostic coincidence rate of ECG was calculated. Results In the observation group, 8 cases were painless, accounting for 12.31%. There were 50 cases of atypical pain, accounting for 76.92%, including 29 cases of subxiphoid pain, 15 cases of irregular chest tightness and concealed pain, 10 cases of mandibular pain, 7 cases of shoulder pain, 4 cases of abdominal discomfort, 2 cases of typical chest back and upper abdominal pain, and 58 cases of atypical ECG. 65 cases in the control group had typical chest, back and upper abdominal pain, and 5 cases had atypical ECG. There were significant differences in painless, atypical pain, typical chest, back and upper abdominal pain and atypical ECG between the two groups (P < 0.05). In the observation group, 63 cases were diagnosed by coronary angiography and ECG, accounting for 96.92%. There was no significant difference between coronary angiography and ECG (P > 0.05). Conclusion ECG is accurate and easy to operate in the diagnosis of atypical myocardial infarction.