BackgroundSARS-CoV-2 caused a pandemic and global threat for human health. Presence of liver injury was commonly reported in patients with coronavirus disease 2019 (COVID-19). However, reports on severe liver dysfunction (SLD) in critically ill with COVID-19 are lacking. We evaluated the occurrence, clinical characteristics and outcome of SLD in critically ill patients with COVID-19.MethodsClinical course and laboratory was analyzed from all patients with confirmed COVID-19 admitted to ICU of the university hospital. SLD was defined as: bilirubin ≥ 2 mg/dl or elevation of aminotransferase levels (> 20-fold ULN).Results72 critically ill patients were identified, 22 (31%) patients developed SLD. Presenting characteristics including age, gender, comorbidities as well as clinical presentation regarding COVID-19 overlapped substantially in both groups. Patients with SLD had more severe respiratory failure (paO2/FiO2: 82 (58–114) vs. 117 (83–155); p < 0.05). Thus, required more frequently mechanical ventilation (95% vs. 64%; p < 0.01), rescue therapies (ECMO) (27% vs. 12%; p = 0.106), vasopressor (95% vs. 72%; p < 0.05) and renal replacement therapy (86% vs. 30%; p < 0.001). Severity of illness was significantly higher (SAPS II: 48 (39–52) vs. 40 (32–45); p < 0.01). Patients with SLD and without presented viremic during ICU stay in 68% and 34%, respectively (p = 0.002). Occurrence of SLD was independently associated with presence of viremia [OR 6.359; 95% CI 1.336–30.253; p < 0.05] and severity of illness (SAPS II) [OR 1.078; 95% CI 1.004–1.157; p < 0.05]. Mortality was high in patients with SLD compared to other patients (68% vs. 16%, p < 0.001). After adjustment for confounders, SLD was independently associated with mortality [HR3.347; 95% CI 1.401–7.999; p < 0.01].ConclusionOne-third of critically ill patients with COVID-19 suffer from SLD, which is associated with high mortality. Occurrence of viremia and severity of illness seem to contribute to occurrence of SLD and underline the multifactorial cause.