Objective：To compare the predictive value of serum albumin（ALB），blood urea nitrogen（BUN）and blood urea nitrogen/ albumin ratio（BAR）for 28-day mortality of patients in trauma green channel，and to construct a model for predicting 28-day mortality by combining the revised trauma score（RTS）. Methods：The clinical data of patients in trauma green channel between January 2020 and December 2020 in the First Affiliated Hospital of Nangjing Medical University were retrospectively analyzed to compare the demographic differences，past history，RTS，injury severity score，and laboratory results between 28-day survival group and death group. The cut-off values of ALB，BUN and BAR were determined by receiver operating characteristic（ROC）curve，and the area under the ROC curve（AUROC）of ALB，BUN and BAR in predicting 28-day mortality was compared by DeLong non-parametric method. The RTS was combined with each of the above three indicators to construct a prediction model respectively，and the Hosmer-Lemeshow test was used to evaluate the model effect and compare the prediction effect of the models. Results：Finally，419 patients were included with 309 men（73.7%），aged（54.3±16.4）years，prehospital time of 4.0（2.0，6.0）h，and 28-day mortality of 7.6%（32/419）. The ROC curve showed that ALB ≤ 29.5 g/L，BUN> 6.97 mmol/L and BAR> 7.39 mg/g were the cut-off values to predict the 28-day mortality of patients in trauma green channel，and the predictive effect of BAR was better than that of ALB and BUN. RTS-ALB，RTS-BUN and RTS -BAR were used to construct the predictive models of the RTS combined with ALB，BUN and BAR，respectively. The predictive effect of these three models was better than that of the RTS，and AUROC of RTS -BAR was the largest，but there was no statistical difference between the AUROC of RTS-BAR and RTS-ALB，and between the AUROC of RTS-ALB and RTS-BUN. Conclusion：BAR is superior to ALB and BUN in predicting 28-day mortality of patients in trauma green channel，and patients with BAR> 7.39 mg/g are indicated poor prognosis. The RTS combined with BAR also has a good value in predicting the prognosis of patients in trauma green channel.