Epilepsy is among the most neurologic disorders. Due to its damaging effects on the brain and the psychological problems that it creates in the patients, it deserves extensive study of its pathogenesis and new therapeutical approaches. The most widely accepted hypothesis on the pathogenesis of epilepsy is a failure in the regulation of excitatory and inhibitory mechanisms in the brain. The aim of this study was to assess the levels of amino acids in cerebrospinal fluid (CSF) which was believed to reflect the levels of excitatory amino acids in the brain. CSF glutamate, aspartate and glycine levels were determined by gas -liquid chromatography in 12 epileptic patients (juvenile myoclonic epilepsy (JME) n=7, idiopathic primary generalized epilepsy with tonic clonic seizuren=5) and 12 controls. In the epileptic patients, glutamate and glycine levels were significantly higher than controls (p The findings of this study suggest that further studies with a larger patient population and comparison of levels in CSF and epileptogenic brain tissue would be useful for a better understanding of the role excitatory amino acids in the pathogenesis of epilepsy