The present disclosure provides a vertical memory structure with air gaps and a method for preparing the vertical memory structure. The vertical memory structure includes a semiconductor stack including a lower semiconductor pattern structure filling a recess on a substrate and protruding from an upper surface of the substrate in a first direction substantially perpendicular to the upper surface of the substrate; a plurality of gate electrodes surrounding a sidewall of the semiconductor stack, the plurality of gate electrodes being at a plurality of levels, respectively, so as to be spaced apart from each other in the first direction; and a plurality of air gap structures disposed at outer sides of the plurality of gate electrodes respectively.