Corticosteroids have always been recommended for severe cases of COVID-19. However, the efficacy of treatment with corticosteroids for COVID-19 during the SARS-CoV-2 omicron outbreak in China has not been reported. Clinical data from 406 patients hospitalized for severe/critical COVID-19 from December 2022 to January 2023 at six hospitals in Chongqing were retrospectively analyzed. The primary outcome was all-cause mortality at 28 days in the groups with and without corticosteroids treatment after propensity score matching (PSM). Secondary outcomes were to compare in-hospital mortality and length of survival time with corticosteroids and those without corticosteroids. This study included 406 patients with severe or critical COVID-19, divided into the corticosteroids group (231, 56.9%) and non-corticosteroids group (175, 43.1%). After PSM, the use of corticosteroids did not reduce all-cause mortality at 28 days (42.5% vs. 39.1%). Univariate analysis showed that corticosteroids were not associated with improved all-cause mortality at 28 days [hazard ratio (HR), 1.019; 95% confidence interval (CI), 0.639-1.623; p = 0.938]. Multivariate analysis showed similar results (HR, 1.047; 95% CI, 0.633-1.732; p = 0.858). Among non-survivors, the survival time was significantly larger in those who received corticosteroids compared with the non-corticosteroid users [median 13 (IQR 6.5-15.5) vs. 6 (4-11.25), p = 0.007]. The use of systemic corticosteroids in severe/critical COVID-19 may provide certain potential survival benefits but does not improve prognosis.