Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Due to its high incidence rate and often long-term sequelae, the TBI contributes significantly to increase costs of health care expenditures annually. Nurses' knowledge and practice play important roles in provision of supportive care to decrease TBI related morbidity and mortality. Aim: the aim of this study was to assess prognostic factors affecting neurological outcomes for patients with closed traumatic brain injury. Study design: Descriptive exploratory study. Subject: A purposive sample of 75 adult patients from both genders regardless their educational level admitted to neurological intensive care unit with moderate to severe closed traumatic brain injury (TBI) based on Glasgow coma scale assessment. Also, a convenient sample of all available nurses (30) working at neurological intensive care unit. Setting This study was carried out in neurological intensive care unit affiliated to Ain Shams University Hospitals, Cairo, Egypt. Tools: (1) Patients related factors tool, Tools: (2) Nurses related factors tool, Tools: (3) Intervention modalities related factors tool & Tools: (4) Neurological outcomes tools Results: advanced age (>=60), diagnosis with (Sub arachnoid, Intracerebral and Diffused brain injury), with odd ratio 4.428, 7.847 ,19.069 and 28.878 respectively as well as the presence of comorbidity with odd ratio 7.847 & CT brain results with odd ratio. 126,.144 and 2.818; are statistically significant predictors of poor prognosis and mortality. Conclusion: Advanced age (>=60), diagnosis with (Sub arachnoid, Intracerebral and Diffused brain injury), Presence of comorbidity & CT brain results, low mean arterial blood pressure, hyperthermia, hyperglycemia, elevated urea level, hyponatremia, hyperkalemia, acidosis, hypercapnia, hypoxia, mechanical ventilation, sedation, surgery and severe baseline GCS are statistically significant predictors of poor prognosis and mortality. Recommendations: Further studies are recommended to assess prognostic factors affecting neurological outcomes for patients with closed traumatic head injury.