Objective: To explore the feasibility of direct renin inhibitor aliskiren for the treatment of severe or critical coronavirus disease 2019 (COVID-19) patients with hypertension. Methods: The antihypertensive effects and safety of aliskiren was retrospectively analyzed in three severe and one critical COVID-19 patients with hypertension. Results: Four patients, two males and two females, with an average age of 78 years (66-87 years), were referred to hospital mainly because of respiratory symptoms. Three were diagnosed by positive novel coronavirus 2019 (2019-nCoV) nucleic acid or antibody, and the critical patient with cardiac insufficiency was clinically determined. Two patients were treated with calcium channel antagonist (CCB), one with angiotensin converting enzyme inhibitor (ACEI), and one with angiotensin Ⅱ receptor antagonist (ARB). After admission, ACEI and ARB were discontinued, one patient with heart failure was treated by aliskiren combined with diuretic.Three patients were treated with aliskiren combined with CCB among whom two withdrew CCB due to low blood pressure after 1 to 2 weeks. Based on comprehensive treatment including antiviral and oxygenation treatment, blood pressure was satisfactorily controlled by aliskiren after three to four weeks without serious adverse events. All patients were finally discharged. Conclusion: Our preliminary clinical data shows that antihypertensive effect of aliskiren is satisfactory and safe for severe COVID-19 patients complicated with hypertension.