A nonvolatile semiconductor memory according to an aspect of the invention comprises a plurality of serially connected memory cells arranged on a P-well area within a semiconductor substrate, select gate transistors connected to one end and the other of the serially connected memory cells, a P-well control circuit which controls the P-well area, a plurality of word lines connected to the plurality of memory cells, a row control circuit which controls the plurality of word lines, and an operation control circuit which controls the P-well control circuit and the row control circuit, wherein, when writing to a selected one of the plurality of memory cells, the operation control circuit controls the P-well control circuit to apply a precharge potential to the P-well area and thus precharge channel areas of the plurality of memory cells.