Objectives: The study was undertaken to investigate the effect of decreased oxygenation status in a patient of head injury and its outcome in terms of prognosis of patients with regards to neurological damage. The objective was to find out a co-relation between the SpO2 levels in a patient on admission and the severity of head injury. Methods: Prospective observational study was carried out after the approval of Institutional ethical committee. Patient with head injury coming to the emergency department of Pravara Rural hospital were assessed for the severity using Glasgow Coma scale (GCS) and hypoxic status by using pulse oximeter with bedside monitors. The SpO2 levels were monitored at 2hrs, 4hrs, 8hrs, 24hrs and 48hrs by pulse oximeter. At the time of discharge outcome was assessed again by Glasgow Outcome Scale (GOS) and the treatment that followed it. Results & Conclusions: Oxygenation status of patient on admission affects the prognosis of the patient in terms of residual neurological deficit as assessed by the Glasgow Outcome scale. There is significant co-relation between the Oxygen saturation at the time of admission and the outcome at the time of discharge. Therefore the SpO2 values are significant in patients with head injury as a prognostic factor.