Provided are a non-volatile memory device and an erasing method thereof. The non-volatile memory device including a memory cell region includes first metal pads and a memory block, the memory block being disposed in a memory cell region and includes a plurality of cell strings having a plurality of memory cells stacked in a direction perpendicular to a substrate between a plurality of bit line and a common source line of the memory block, and a peripheral circuit region including second metal pads and a control logic, and vertically connected to the memory cell region by the first metal pads and the second metal pads, wherein the control logic configured to, perform control such that a first erase voltage is provided to the plurality of bit lines and the common source line, and a first erase control voltage is provided to a plurality of first selection lines and a second selection line during a first erase period, the plurality of first selection lines being used for selecting a corresponding cell string from among the plurality of cell strings and the second selection line being disposed closest to the common source line, and perform control such that a second erase voltage is provided to the plurality of bit lines, and such that a second erase control voltage is provided to at least one first selection line among the plurality of first selection lines during a second erase period, the second erase control voltage being lower than the first erase control voltage.