Abstract: Objective To explore the ECG criterions for the diagnosis of left ventricular hypertrophy. Methods In the Second Affiliated Hospital of Wenzhou Medical University from June, 2015 to June, 2016,166 patients with high voltage left ventricle were diagnosed by electrocardiogram, and the sensitivity and specificity of different morphological ECG criteria were evaluated by echocardiography as the "gold" standard. Results Echocardiography revealed 81(48.79%) of left ventricular hypertrophy in 166 patients who were diagnosed by electrocardiogram (ECG) as left ventricular high voltage. Among them, there were 126 cases of Sokolow index, 75 cases were left ventricular hypertrophy, and the positive rate was 59.52%. The diagnostic accuracy, specificity and sensitivity were 62.66%, 40%, 92.59% respectively, and 82 cases conformed to the Sokolow index with ST-T change, and the positive detection rate was 70.73%, higher than Sokolow. The positive detection rate, accuracy, specificity and sensitivity of ECG were 71.69%, 71.76% and 71.60% respectively. There were 91 cases of Sokolow index with ST-T and Cornell index. The positive rate was 83.52%, which was significantly higher than the positive rate of the previous two methods. The accuracy, specificity and sensitivity of Sokolow index with ST-T and Cornell index were 87.95%, 82.35%, and 93.82% respectively. Compared with the accuracy, specificity and sensitivity of the former method, the difference was statistically significant(P<0.05). Conclusion Electrocardiogram Sokolow index combined with ST-T changes and Cornell index can greatly improve the accuracy, sensitivity and specificity of diagnosing left ventricular hypertrophy, and even to a certain extent, assess the degree and severity of hypertrophy, which is worthy of clinical application and promotion.