Background: The initial mechanism of COVID-19 is the binding of the virus to ACE2. Since the heart and the vessels also express ACE2, they both could become targets of the virus. However, cardiac performance of mild and severe patients may be different, requested individualized treatment. The aim of this study is to explore the global and segmental myocardial performance of the severe and mild COVID-19 patients.Methods: 45 patients with COVID-19 infection were included in this study. The clinical history, laboratory test and standard and strain echocardiography were performed at admission. Results: 1. All patients showed reduced cardiac diastolic function; 2. Severe patients exhibited exacerbated right ventricular systolic function; 3. All patients showed impaired left ventricular strain, worse strain in severe patient. 4. The apical longitudinal strain of mild patients was higher than basal and middle segment. 5. There was a negative correlation between LV GLS and log TnT-hs, as well as NT-pro BNP. 6. The EF value and strain of left atrium of mild and severe patients decreased; 7. LV GLS, LV GCS and LA GLS area under the ROC curve to predict the disease severity were 0.698, 0.758 and 0.782 respectively. 8. In the follow-up of severe patients, left atrial and ventricular strain showed an increased trend.Conclusions: These findings suggested that left ventricular performance was subclinically impaired during COVID-9 infection irrespective of infection severity and the strain of LV and LA may predict the disease severity. The cardiac function had an increasing trend for severe patients.