Amubarvimab-romlusevimab is used antiviral regimens currently recommended in China for the treatment of adult patients with mild or moderate SARS-CoV-2 infections who are at a high risk factor for progression to severe COVID-19, but its exact efficacy in patients with severe COVID-19 is not yet known. This is a single-center retrospective cohort study. A total of 121 patients in intensive care units(ICU) diagnosed with severe COVID-19 were evaluated.The amubarvimab-romlusevimab therapy can reduce the 14-day mortality（23.40% vs 41.89%, p=0.037）, 28-day mortality（29.79 % vs 51.35%，p=0.02）, and ICU mortality（29.79% vs 55.41%，p=0.006) of severe COVID-19. To reduce bias and make the two groups balanced and comparable, a 1:1 PSM was performed. In the matched population（n=47), there were no statistically significant differences between the mAbs (monoclonal antibody)group and the Non-antiviral group in 14-day, 28-day, and thromboembolic events in COVID-19 patients. The 40-day survival analysis shows that mAbs therapy can improve patient prognosis (HR=0.45, 95%CI=0.26-0.76, p=0.008). However, no significant intergroup difference in the 40-day cumulative viral conversion rate. In a univariate Cox regression analysis, The Amubarvimab - romlusevimab therapy( HR:0.464; CI:[0.252-0.853];p:0.013),CRP, PCT, PLT, Lactate, PT, PT-INR, and pt% level at admission were risk factors for clinical prognosis. After including the above covariates, Multifactorial COX regression shows that the Amubarvimab - romlusevimab therapy( HR:0.464; CI:[0.252-0.853];p:0.013), CRP, Lactate and PT-INR at admission are independent factors for mortality of severe COVID-19. Based on the current data, we conclude that amubarvimab-romlusevimab therapy is beneficial for patients with severe COVID-19.