Sodium (23Na) MRI has been proposed as a potential imaging modality for the characterization of hepatic tumors and for monitoring therapy response. Up to now, only one study has been performed on implanted hepatocellular carcinomas in rats. In the present work, in-vivo 23Na MRI of the healthy human liver is performed and to the best of our knowledge, the hepatic tissue sodium concentration is estimated for the first time. For quantitative 23Na MRI correction methods were applied such as self-gating and B1+ correction. The mean sodium concentration for three volunteers was estimated to be (27±5) mM in the liver.