Gelsolin is an actin regulatory protein that generally distributed in a wide variety of body tissues, especially the brain tissues and cerebrospinal fluid. In this study we found that lumbar CSF-gelsolin concentrations markedly decreased in epileptic patients by enzyme linked immunosorbent assay. In order to help judge the result, we determined gelsolin expression in temporal lobe tissues of patients with temporal lobe epilepsy using double-label immunofluorescence to location and using western blot to quantitation. Then we observed that gelsolin was co-expressed with microtubule-associated protein-2 in axons and cytoplasms of neurons and gelsolin protein level was also down-regulated in temporal lobe tissues of epileptic patients. Our findings suggested that CSF-gelsolin level might reflect the alteration of gelsolin in brain tissue of epileptic patients and CSF-gelsolin seems to be a potential biomarker for epilepsy.