The purpose of this study was to evaluate the diagnostic performance of emergency medical service (EMS) assessed symptoms of cardiovascular disease for actual acute myocardial infarction (AMI). Patients from 2008 to 2012 transported to 4 study hospitals by EMS were included. Using EMS records and ED database, all patients were stratified according to the presence of EMS assessed cardiac symptoms and ED diagnosis of AMI. Disproportionate stratified sampling was used and hospital record of sampled patients were reviewed to identify the actual diagnosis of AMI. Using the inverse probability weighting, verification bias-corrected diagnostic performance were estimated. Overall, 92,353 patients were enrolled for the study. Of these, 13,971 (15.1%) complained cardiac symptoms to EMS provider. 775 patients were sampled for hospital record review. The sensitivity of EMS provider assessed cardiac symptom on the final diagnosis of AMI was 73.3% (95% CI: 70.8 to 75.7), specificity was 85.3% (95% CI: 85.3 to 85.4), positive predictive value was 3.9% (95% CI: 3.6 to 4.2), and negative predictive value was 99.7% (95% CI: 99.7 to 99.8). We found that EMS provider assessed cardiovascular symptoms had moderate sensitivity and specificity for diagnosis of AMI.