According to the domestic as well as foreign reports, pediatric neurological diseases might be misunderstood as those of the distant and rare illnesses to primary physicians, however, they account for 3~4% of pediatric outpatients visit, which means pediatric neurological diseases are not uncommon. The most leading neurological cause of pediatric clinic visits is convulsive disorder, followed by head trauma, behavioral problems and psychosomatic disorders, congenital anomalies with neurological manifestations, developmental delay including cerebral palsy, CNS infections, perinatal neurologic disorders, cerebral degenerative diseases, and so on. Because these statistical results excluded neurological diseases detected at personal or collective medical checkup and nursing-health consultation, the neurological diseases actually account for over 4% of pediatric outpatient visits. The need for improvement both in range and quality of primary care, and of early diagnosis and prevention of chronic disease is increasing, gradually outdating disease-oriented medical approach in the past. The patients and their families should have preliminary knowledge on their particular diseases since the medical expertise is spreading along the advance of mass media and information technology. Therefore, they are hardly satisfied if primary physician simply explains that 'seizure due to fever' is called 'febrile convulsion', or 'children with subnormal intelligence' are regarded as 'mental retardation'. Therefore, physicians should illustrate the cause of illnesses, the extent of symptoms, differential diagnoses, complications, prognoses, as well as sequelae. Here the author briefly describes the differential diagnoses of the most common symptoms-seizure, developmental delay and headache.