Introduction: Although intensive care units (ICUs) are where severe and complicated cases are managed, there is limited evidence on treatment outcomes in Ethiopia. Therefore, this study is aimed at assessing the magnitude and associated factors of mortality among patients with sepsis admitted to ICUs at southern Amhara public hospitals, Ethiopia.Methods: A total of 547 medical records of patients with sepsis admitted to the ICUs at Injibara, Debre Markos, and Debre Tabor hospitals in the past 3 years were retrieved from August 10–31, 2022. Multivariable logistic regression analyses were conducted and adjusted odds ratios (AOR) with a 95% confidence interval (CI) were reported, and a p value < 0.05 was set to declare the significance of the association.Results: In this study, 46.2% (95% CI: 41.7%–50.3%) of patients with sepsis died during their ICU stay. Respiratory, gastrointestinal, and urinary tract infections contributed to 32.3%, 25.8%, and 9.6% of mortality, respectively. Individuals aged 60 and above (AOR: 4.07; 95% CI: 2.23–7.44), those with a Glasgow Coma Scale ≤ 10 at admission (AOR: 11.27; 95% CI: 4.64–27.37), respiratory site of infection (AOR: 5.38; 95% CI: 2.94–9.86), creatinine level > 1.1 mg/dL (AOR: 4.20; 95% CI: 2.33–7.60), vasopressor use (AOR: 3.13; 95% CI:1.66–5.95), initiation of antibiotics 1–3 h after admission (AOR: 2.80; 95% CI: 1.64–4.76), and a hospital stay of more than 20 days (AOR: 3.44; 95% CI: 1.40–8.46) were significantly associated with mortality.Conclusion: Overall, the mortality rate among patients with sepsis admitted to ICUs in southern Amhara public hospitals was high. Mainly, death was attributed to respiratory infections. Elderly patients and those with deteriorated clinical conditions at admission were at higher risk. Therefore, special attention is needed for elderly patients admitted with respiratory infections, antibiotics should be initiated as early as possible, and interventions must be designed to shorten the length of stay in ICUs.