Blood pressure variability (BPV) is essential in hypertensive patients and is frequently associated with organ damage. As of today, hypertension is still the most common comorbidity in COVID-19, but the impact of BPV and the therapeutic target of BPV on outcomes in COVID-19 patients with hypertension remain unclear. Therefore, this study investigated the relationship between BPV and severity of COVID-19, in-hospital mortality, hypertensive status, and efficacy of antihypertensives in suppressing hypertensive covid-19 patient BPV. This cohort retrospective study enrolled 351 patients hospitalized with COVID-19. Subjects were classified according to the severity of COVID-19, the presence of hypertension, and their BPV status. During hospitalization, mean arterial pressure (MAP) was measured at 6 a.m. and 6 p.m., and BPV was calculated as the coefficient of variation of MAP (MAPCV). MAPCV values above the median were defined as high BPV. In addition, we compared the hypertensive status, COVID-19 severity, in-hospital mortality, and antihypertensive agents between the BPV groups. The mean age was 53.85 ± 18.84 years old. Hypertension was significantly associated with high BPV with prevalence ratio (PR) = 1.38 (95% CI = 1.13–1.70; p = 0.003) or severe COVID-19 (PR = 1.39; 95% CI = 1.09–1.76; p = 0.005). In laboratory findings, high BPV group had lower Albumin, higher WBC, serum Cr, CRP, and creatinine to albumin ratio. High BPV status also significantly increased risk of mortality (HR = 2.30; 95% CI = 1.73–3.86; p < 0.001). Patients with a combination of severe COVID-19 status, hypertension, and high BPV status had the highest risk of in-hospital mortality (HR = 3.51; 95% CI = 2.32–4.97; p < 0.001) compared to other combination status groups. In COVID-19 patients with hypertension, combination therapy with calcium channel blockers (CCB) as well as CCB monotherapy significantly develop low BPV (PR = 2.002; 95 CI% = 1.33–3.07; p = 0.004) and low mortality (HR = 0.17; 95% CI = 0.05–0.56; p = 0.004). Hypertensive status and severe COVID-19 were significantly associated with high BPV, and these factors increased in-hospital mortality. CCBs might be antihypertensive agents that potentially effectively suppressing BPV and mortality in COVID-19 patients.