Hyperbilirubinemia is frequently reported in trauma patients. However, few studies have investigated the effects of hyperbilirubinemia on patients’ clinical trajectories. This study aimed to evaluate the relationship between hyperbilirubinemia and patient outcomes following trauma. Our study included 387 patients who were admitted to the trauma bay with severe trauma between January 2017 and December 2021. We categorized patients into two groups based on their peak bilirubin levels: the low-bilirubin (LB) group, with levels below 3 mg/dL, and the high-bilirubin (HB) group, with levels above 3 mg/dL. We then compared the rates of complications and mortality between these two groups. The incidence of pneumonia (10.8% vs. 32.3%,p< 0.001), acute kidney injury (AKI) (2.8% vs. 19.2%,p< 0.001), sepsis (2.8% vs. 10.1%,p= 0.003), and wound infections (8.3% vs. 30.3%,p< 0.001) was significantly higher in the HB group. Additionally, the mortality rate was significantly higher (4.2% vs. 10.1%,p= 0.028) in the HB group. Multivariate analysis revealed that the higher the bilirubin level, the greater the risk of complications (pneumonia: odds ratio [OR] = 3.238; 95% confidence interval [CI] = 1.68–6.22;p< 0.001, AKI: OR = 4.718; 95% CI = 1.65–13.44;p= 0.004, sepsis: OR = 3.087; 95% CI = 1.00–9.52;p= 0.04, wound infection: OR = 3.995; 95% CI = 2.073–7.700;p< 0.001). In conclusion, hyperbilirubinemia was associated with poorer outcomes in trauma patients.