Background: Trauma is injury to living tissue caused by an extrinsic agent. Trauma is a Greek word which means body injury. Blunt chest trauma causes 25% of traumatic deaths. It is commonly associated with multiple organ damage which leads to catastrophic patient outcome. Blunt chest trauma is more common than penetrating chest trauma. Arterial blood gas (ABG) studies report the degrees of acidemia, hypercarbia, and hypoxemia, which depend on cardiopulmonary status at the time of collection.  Objective: To determine the value of ABG measurements in patients with blunt chest trauma and its role in prognosis of different outcomes. Patients and Methods: This study included 100 patients arrived to Emergency Department (ED) in Emergency Hospital-Mansoura University during the period from 1-8-2019 to 1-8-2020. Patients were divided to subtypes according to ward or ICU admissions and presence or absence of lung injury. Length of hospital stay as outcome was also reported. Results: ABG and combined ABG measurements are strongly reflecting the clinical situation of chest trauma patients. It can predict longer length of hospital stay. PCO₂ is more sensitive than HCO3^- in prediction of ICU admission in chest trauma patients. SaO₂, combined ABG analysis had higher sensitivity in prediction of ICU admission in chest trauma patients. HCO3^- level and combined ABG were statistically significant in prediction of lung injury among studied patients with high specificity. Conclusion: ABG values and combined ABG values seemed to have a promising role in determination of patients admitted to ward versus others admitted in ICU.