A method for fabricating a non-volatile memory device includes alternately stacking a plurality of inter-layer dielectric layers and a plurality of sacrificial layers over a substrate, forming at least a channel hole that exposes the substrate by selectively etching the inter-layer dielectric layers and the sacrificial layers, forming a protective layer on sidewalls of the sacrificial layers that are exposed through the channel hole, sequentially forming a memory layer and a channel layer on the sidewalls of the channel hole, forming slit holes that penetrate through the inter-layer dielectric layers and the sacrificial layers on both sides of the channel hole, removing the sacrificial layers that are exposed through the slit holes, removing the protective layer, and forming gate electrodes in space from which the sacrificial layers and the protective layer are removed.