A vertical memory device includes a gate structure on a peripheral circuit region of a substrate, the substrate including a cell region and the peripheral circuit region, and the gate structure including a first gate electrode, second, third, and fourth gate electrodes sequentially disposed at a plurality of levels, respectively, on the cell region of the substrate in a vertical direction substantially perpendicular to an upper surface of the substrate, a first epitaxial layer extending through the second gate electrode on the cell region of the substrate, a channel extending through the third and fourth gate electrodes in the vertical direction on the first epitaxial layer, and a second epitaxial layer on a portion of the peripheral circuit region of the substrate adjacent the gate structure.