Objective: To investigate the clinical value of Glasgow Coma Scale-Pupil Response (GCS-P) score in patients with severe brain injury in intensive care unit (ICU). Methods: We reviewed the general data of 160 patients with severe brain injury admitted to ICU in our hospital, and analyzed the correlation between GCS score, P score, GCS-P score and 28-day mortality rate, and the unfavorable late outcomes on the GOS score in the 3rd month after injury. Results: Separately, the GCS score, P score, and GCS-P score were each negatively correlated with the 28-day mortality rate and the unfavorable late outcomes on the GOS score in the 3rd month after injury. The correlation coefficient between GCS-P score and mortality rate and unfavorable late outcomes rate was greater than GCS score. When the GCS score is the same as the GCS-P score, in addition to 4 points, the GCS-P score has a higher mortality rate and unfavorable late outcomes rate. Patients with a GCS score of 3 points had a lower mortality rate and a lower unfavorable late outcomes rate than patients with a GCS score of 4 points. But the result was not observed in the GCS-P score. Conclusion: The correlation between GCS-P score and mortality rate and unfavorable late outcomes rate is better than GCS score. It provides more information than GCS score. The evaluation scope is larger, and it is simple and practical. It is of great value for clinical rapid assessment of the condition and prognosis of patients with brain injury.