Angiotensin converting enzyme 2（ACE2） is an important member of renin-angiotensin system（RAS） in human body，and its physiological function is mainly to catalyze the conversion of angiotensin （Ang）Ⅱ to Ang-（1-7）. The massive outbreak of the novel coronavirus and its rapid infectious capacity have made it a major public health emergency of global concern. According to statistics，a quarter of the patients have complications，and hypertension is the most common one. The novel coronavirus invades cells by binding to ACE2 on the cell membrane of the human mucosal epithelium and replicates in large numbers inside of cells to produce pneumonia. Its infectivity is strong，and at present，there are still not the definite effective treatment way. In patients with COVID-19，the ACE/Ang Ⅱ/AT1R axis and ACE2/Ang-（1-7）/Mas axis are out of balance. According to our previous study results and the findings from other laboratories，we find that Ang-（1-7） protects cardiopulmonary function，relaxes blood vessels，decreases blood pressure and up-regulates ACE2 expression. Exogenous administration of Ang-（1-7） might not only alleviate and reverse the imbalance of RAS inside of the human body，but also play a supporting and protective role in the pulmonary and cardiovascular systems. Therefore，we speculate that Ang-（1-7） has the potential to treat or relieve the COVID-19 in patients with hypertension.