New non invasive methods are required to better delimit the epileptogenic zone (EZ) during the pre-surgical exam of epileptic patients. By combining ex vivo NMR spectroscopy-based (MRS) untargeted metabolomics and in vivo MRS-based targeted metabolomics, we found that GABA was the most discriminant metabolite of the epileptogenic zone vs adjacent brain regions in a mouse model of mesio-temporal lobe epilepsy (MTLE). GABA appears therefore as a specic in vivo biomarker of EZ in MTLE.