The EEG is the most important means of diagnosing epilepsy and seizures, and is also an important basis for the “international classification” of epilepsy and seizures, as well as a reference for determining the response to treatment and reducing and stopping medication. However, the diagnosis of epilepsy should not be based solely on the presence of epileptiform discharges on the EEG. A normal EEG does not mean that epilepsy can be ruled out. Therefore, standardized EEG examinations should be performed, including various evoked tests, extended EEG recording time, and EEG recording under special conditions (different sleep depths). 2.Imaging examination Cranial CT: It can find more obvious structural abnormalities, but it is difficult to find subtle structural abnormalities. MRI has a high spatial resolution and can detect subtle structural abnormalities, which has a high reference value for etiologic diagnosis, especially for the evaluation of refractory (intractable) epilepsy. A variety of different imaging techniques and sequences have been used in clinical testing, and their diagnostic significance varies for structural abnormalities (lesions) of different nature, such as hippocampal sclerosis, focal cortical dysplasia, cavernous hemangioma, nodular sclerosis, cerebral surface hemangiomatosis, smoker’s disease, and mitochondrial encephalopathy. 3. Neuropsychological examination Many children with epilepsy are accompanied by intellectual and psychiatric behavioral abnormalities, which need to be evaluated with specialized methods. The diagnosis of certain epileptic syndromes and epileptic encephalopathies requires the support of neuropsychological findings. In patients undergoing preoperative evaluation for epilepsy, neuropsychological assessment not only helps to localize the epileptogenic focus, but also helps to evaluate changes in various brain functions before and after surgery. 4. Head PET allows quantitative analysis of biochemical processes in specific functional brain areas and can be interpreted as an examination of brain cell activity. In addition PET examination can help to detect microscopic lesions that are difficult to detect by MRI. 5. Other laboratory tests Hematological tests including routine blood, blood glucose, electrolytes and blood calcium can help to find the cause of the disease. Blood concentration monitoring of antiepileptic drugs helps in drug adjustment and detection of drug toxicity, etc. Hematological tests are also used for the detection of adverse drug reactions, and common monitoring indicators include blood routine, liver and kidney function and electrolytes. Seizures are one of the main manifestations of genetic metabolic disorders. Blood and urine genetic metabolic screening can help diagnose the etiology of epilepsy. A portion of epilepsy is genetically related, especially certain specific types of epilepsy, and genetic screening is needed to confirm the diagnosis and to complete further genetic counseling and guidance.