The causes of moderate EEG abnormalities in pediatric patients are generally physiologic and pathologic. Pathologic moderate EEG abnormalities are mainly due to central nervous system infections, epilepsy, and intracranial abnormalities. Moderate EEG abnormalities also include many types, such as slow background activity waves, broad spikes, spikes and slow waves, etc. Physiologic EEG abnormalities can be seen in children who are normal and do not have any other neurological symptoms, as well as do not have any craniocerebral diseases, and can be manifested as abnormal EEG rhythms or an increase in the number of slow waves. Pathological causes include central nervous system infections such as viral encephalitis, purulent meningitis, etc.; intracranial abnormalities including brain tumors, etc.; epileptic EEG can show extensive epileptiform discharges; EEG abnormalities can be caused by toxic encephalopathy, increased intracranial pressure, traumatic brain injury, cerebral hemorrhage, and cerebral edema. Children with moderate EEG abnormalities need to consult the doctor in time, undergo relevant examinations, and receive targeted treatment after the cause of the disease is clarified in time.