Introduction: Our aim was to evaluate the impact of corticosteroids on clinical course and outcomes of patients with severe community-acquired pneumonia (CAP) requiring invasive mechanical ventilation. Methods: This was a cohort study of patients with severe CAP from 2 intensive care units in tertiary hospitals in Brazil and Portugal. Results: A total of 111 patients were included (median age, 69 years; 56% men; 34% hospital mortality). Corticosteroids were prescribed in 61 (55%) patients. Main indications for their use were bronchospasm (52.5%) and septic shock (36%). Mortality rate of patients treated with and without corticosteroids was comparable (29.5% vs 32%, P = .837). No significant differences were observed on clinical course from day 1 to day 7 as assessed by the Sequential Organ Failure Assessment score (P =.95). Furthermore, C-reactive protein declined similarly in both groups (P = .147). In a multivariate analysis, mortality was associated with older age and higher Acute Physiology and Chronic Health Evaluation II score. Conclusions: In patients with severe CAP requiring invasive mechanical ventilation, adjunctive therapy with corticosteroids did not influence intensive care unit and hospital mortality. In addition, no changes were observed on weaning from vasopressors, on recovery from organ failure/dysfunction as assessed by the Sequential Organ Failure Assessment score, as well as on C-reactive protein course.