BACKGROUND Acute kidney injury (AKI) is a common cause of organ failure in patients after major trauma and is associated with increased morbidity and mortality. Early identification of patients at risk enables the implementation of a bundle of supportive care, which reduces the incidence of AKI. The primary objective of our study was to investigate whether the levels of biomarkers on admission predicted the onset of early AKI in patients with serious injuries. MATERIAL AND METHODS This prospective observational study included 98 adult patients of both sexes with a serious injury (injury severity score >16). At admission, blood samples were taken, and creatinine, neutrophil gelatinase-associated lipocalin (NGAL), high mobility group box 1 (HMGB-1), and markers of rhabdomyolysis (creatine kinase, myoglobin) were evaluated. The patients were provided with standard resuscitation care, and the occurrence of AKI was monitored during the first 7 days after admission to the Intensive Care Unit, according to the Kidney Disease Improving Global Outcomes diagnostic criteria. RESULTS AKI occurred in 25 (25.5%) patients, in whom the admission levels of HMGB-1, NGAL, creatinine, and myoglobin were significantly higher than in non-AKI patients (48.3±98.4 vs 113.0±209.4 µg/L, P=0.006; 150.2±349.9 vs 181.4±152.2 µg/L, P=0.004; 83.1±20.8 vs 118.8±32.2 µmol/L, P<0.005; 2734.4±2214.5 vs 4182.3±2477.1 µg/L, P=0.008, respectively). Creatine kinase was 14.5±9.2 µkat/L in non-AKI patients and 13.7±7.9 µkat/L in AKI patients (P=0.916). CONCLUSIONS Admission levels of HMGB-1, NGAL, creatinine, and myoglobin predicted the risk of AKI in severely injured patients.