Background: Traumatic brain injury (TBI), defined as an alteration in brain functions caused by an external force, (1) is responsible for high morbidity and mortality around the world, TBI is an extremely important cause of mortality and morbidity in the developed world. The candidate genes affecting TBI outcomes including apolipoprotein E (APO E), P53, angiotensin I-converting enzyme (ACE), D2 subtype of the dopamine receptor (DRD2), atechol-O- methyltransferase (COMT), BCL-2, neuroglobin (NGB) and IL-1β. Also some biochemical changes may occur in patients with TBI, such like electrolytes and blood glucose. Materials and methods: This is a cross-sectional study that had been conducted at the National Center for Neurological Sciences (NCNS) during January 2016 to March 2016, Blood specimens were obtained from 51 TBI patients treated at NCNS, and processed for biochemical profile and molecular genotyping of p53 gene Arg/pro. Results: Molecular screening of P53 gene codon 72 at exon 4 showed that the most common allele was arginine (Arg/arg). In the present study measurement of sodium and potassium revealed that, sodium level < 135mmol/l was detected in 3.9% and >145 was 15.7% of TBI patients, potassium level <3.5 was detected in 25.5% of TBI patients.