Abstract: As an important advance in the treatment of anti-tumor therapy, immune checkpoint inhibitors significantly prolong the survival of patients with malignant tumors. At the same time, immune-related adverse reactions are also increasing, among which ICIs have increased the risk of acute coronary events, but clinical reports are rare. This paper analyzes the history of a patient with pulmonary small cell neuroendocrine carcinoma who developed acute myocardial infarction after ICIs treatment, suggesting that clinicians should be alert to the occurrence of ICIs-related acute myocardial infarction, and improve the prognosis of patients through early identification and intervention.