Objective To understand the pre-hospital symptoms and medical-seeking characteristics of young and middle-aged patients with acute myocardial infarction, so as to provide a reference for medical staff conducting targeted health education to improve patient delays in seeking medical attention. Methods Adhering to inclusion and exclusion criteria, electronic medical records of 200 young and middle-aged acute myocardial infarction patients were extracted from the hospital′s medical big data platform. Text mining was performed on the unstructured textual information within the electronic medical records, then frequency analysis and visualization techniques were employed to analyze patients′ pre-hospital symptoms and medical-seeking behavior. Results Chest pain and tightness were identified as the typical and specific symptoms of young and middle-aged patients with acute myocardial infarction, while profuse sweating, fatigue, and palpitations were among the less common but strongly related pre-hospital symptoms. A total of 148 patients sought local medical attention and were subsequently referred to higher-level hospitals for further diagnosis and treatment. Conclusion The young and middle-aged patients with acute myocardial infarction exhibit varying degrees of typical and atypical symptoms prior to seeking medical care, and their medical-seeking behavior is related to the severity of their condition. The medical big data platform demonstrates unique advantages in terms of operational convenience and data acquisition capabilities, however, the quality of data still requires improvment.