Homocysteine is an intermediate product of methionine and cysteine metabolism, and plays a key role in methylation. Epilepsy is one of the common diseases of the nervous system, long-term repeated seizures will not only cause damage to the brain tissue, but also cause cognitive impairment. At present, the clinical treatment for epilepsy is still mainly to control symptoms, the fundamental etiology of epilepsy still needs to be improved, to explore the etiology of seizures, fundamentally control seizures, is still our long-term struggle direction. High homocysteine is associated with many diseases. Epidemiological studies have shown that the serum homocysteine level of 10% ~ 40% of epilepsy patients is higher than that of the normal population. By exploring the relationship between serum Hcy and epilepsy,We expect to provide help for the diagnosis and treatment of clinical epilepsy.