A method is for operating a nonvolatile memory device, the nonvolatile memory device including at least one string connected to a bit line, the at least one string including a plurality of memory cells connected in series, each of the plurality of memory cells being connected to a respective word line among a plurality of word lines and stacked in a direction perpendicular to a substrate. The method includes applying a word line voltage needed for an operation to a first word line among the word lines, applying a recovery voltage higher than a ground voltage to the first word line after the operation, and then floating the first word line.