The present invention discloses a method for detecting and examining traumatic brain injury (TBI) in vitro. The method is according to the principle of expression of Etk/Bmx protein which is correspondingly increased when TBI occurs, so that the Etk/Bmx protein is defined as a quantification reference indicator specific for neurological injury degree of TBI. Thus, the method can be used to detect the expression of the Etk/Bmx protein for examining and evaluating the neurological injury degree of TBI occurred due to an external impact.