Differences in the diagnostic value of various electrocardiographic (ECG) voltage indices for hypertrophic cardiomyopathy (HCM) are yet to be elucidated. The objective of this study was to examine the strongest predictor within ECG voltage criteria for left ventricular hypertrophy (LVH) in HCM to be applied in cardiovascular examination of young people. The electrocardiograms of 36 healthy individuals with high voltages, mimicking HCM (i.e., false-positive), were statistically compared with those of 30 subjects with an ECG diagnosis of HCM. The most striking ECG voltages observed in HCM patients were those included in leads DI, aVL (R wave) and V3 (S wave) (P<0.001), typically present in the Cornell, Gubner and Lewis voltage criteria. In a stepwise logistic regression analysis model, these indices were the most significant predictors of HCM (P<0.001, P<0.027 and P<0.006, respectively). The combination of Cornell (RaVL+SV3>2.8 mV in men and>2.0 mV in women) with Lewis (RI+(''')SIII-RIII-SI>1.7 mV) or Gubner-Ungerleider (RI+(''')SIII>2.5 mV) indices displayed the highest net sensitivity (80.0% and 76.7%, respectively) while retaining excellent specificity (88.9% and 91.6%, respectively). In conclusion, the combination of the Cornell and the Lewis or Gubner voltage criteria showed the greatest net sensitivity and specificity for the LVH diagnosis of HCM in a cardiovascular examination conducted in young people.