Objective To investigate the clinical features of young female patients with acute myocardial infarction (AMI) who were referred to Peking Union Medical College Hospital. Methods A total of 24 consecutive AMI female patients (age≤44 years) who underwent coronary angiography were retrospectively retrieved from the database, and 70 AMI patients whose age ≥ 65 years and who also underwent coronary angiography were enrolled as a control (elderly) group. Clinical features were compared between the two groups. Results Of the 24 young female AMI patients, MI from non-atherosclerosis was identiifed in 9 patients (non-ATS group). Compared to the remaining 15 young female AMI patients (ATS-group), non-ATS group was younger (P<0.05), with lower BMI (P<0.05) and less traditional risk factors of coronary heart disease (P<0.05). Coronary angiography showed more normal artery (P<0.05) and lesions on left main (P<0.05). However, when compared to the elderly group, the young female ATS-group was associated with less hypertension (P<0.01), smoking (P<0.05), traditional risk factors (P<0.01) and lower level of blood pressure (P<0.05), fasting glucose (P<0.05), serum creatine (P<0.01), TC (P<0.05), and LDL-C (P<0.01) at admission. Coronary angiography showed single vessel disease was the most common lesion. Conclusions Acute myocardial infarction in young female might be caused by non-atherosclerosis. Those due to atherosclerosis differ in coronary risk factors and angiographic features from the elderly female AMI patients.