A nonvolatile memory includes a first bit line coupled to a first cell string, a second bit line coupled to a second cell string, and a bit line precharge unit configured to precharge the first bit line and the second bit line before a program operation. A bit line selected from among the first bit line and the second bit line is precharged to a lower voltage level than a target voltage level, and an unselected bit line is precharged to the target voltage level.