Objectives: The main aim of our study is to observe clinical characteristics and effects of antihypertensive drugs in different hospitalized populations, and to further provide evidence to explore causes and specific clinical markers of the aggravation of COVID-19 in patients with underlying hypertension. Design: This was a retrospective cohort study focusing on the clinical data of COVID-19 inpatients admitted at the early stage of pandemic. Setting: A single center study conducted in Tongji Hospital, Tongji Medical College of Huazhong university of Science and Technology (Wuhan, China). Participants: All 1031 inpatients diagnosed with COVID-19 according to Prevention and control Scheme for Novel Coronavirus Pneumonia published by National Health Commission of the People' s Republic of China and WHO interim guidance in Tongji hospital (Wuhan, China), from January 27, 2020, to March 8, 2020 with the cutoff date being March 30, 2020, were included in this study. Main outcome measures: Demographic data, medical history, clinical symptoms and signs, laboratory findings, chest computed tomography (CT), treatment, and clinical outcomes were extracted from electronic medical records. Results: 1031 COVID-19 inpatients were included in this study, of whom 866 were discharged and 165 were deceased in hospital. 73% of 165 deceased patients had chronic comorbidities. Patients with underlying diseases showed CFR 2.8 times as that of patients without. Senility and males were observed to be main risk factors for increased in-hospital case-fatality rate, with the odds ratio in multivariable regression being 2.94 (95%CI: 2.00 to 4.33; P <0.001) and 2.47 (95%CI: 1.65 to 3.70; P <0.001), respectively. The odds ratio of cases with composite endpoints for patients with simple hypertension was 1.53 (95%CI: 1.07 to 2.17; P=0.019). Senile patients with hypertension were proved to be at high risk early in the disease, which might be associated with the level of CRP, LDH, and eGFR. The odds ratio of case-fatality rate for patients with hypertension taking CCB group was 0.67 (95%CI: 0.37 to 1.20; P = 0.176). Among 271 severe cases without IKF, the odds ratio of case-fatality rate was 0.42 (95CI%: 0.18 to 0.99; P = 0.046) for patients in the CCB group after adjustment of age, sex, and underlying diseases. Conclusions: Hypertension is not just a chronic underlying comorbidity, but also a risk factor affecting the severity of COVID-19 and does play a critical role in worsening patients' clinical outcomes. Therefore, hypertension management in patients with COVID-19 should be regarded as a major challenge in the diagnostic and therapeutic strategies.