The examination related to infant brain injury mainly includes physical examination, lumbar puncture cerebrospinal fluid examination and imaging examination, and electroencephalogram examination. When the infant brain injury firstly need to carry out a more detailed physical examination, such as whether the infant is awake or unconscious, whether there is any laceration or hemorrhage on the head, observing the size of the pupil and the change of the light reaction, whether the neck is soft or straight, and the muscular strength and muscle tone of the infant’s limbs. Lumbar puncture in the early stage of infant brain injury in the cerebrospinal fluid can be found in a large number of red blood cells, help to determine whether there is craniocerebral injury and bleeding. It is diagnostic for diseases such as purulent meningitis. More common are imaging tests, such as cranial CT or magnetic resonance imaging. The results are intuitive, accurate and non-traumatic to the infant, and are commonly used in clinical practice.CT is more sensitive to hemorrhage and MRI is more effective in imaging brain tissue. Electroencephalography (EEG) can be performed if necessary to assist in the diagnosis. Brain injuries in infants require immediate medical attention due to the severity of the condition and the potential for rapid progression.