A nonvolatile semiconductor memory device comprises a memory cell array in
which memory cells are arranged in a row and column direction, a circuit
for applying a first voltage to a selected bit line, a circuit for
applying a second voltage to unselected bit lines and word lines, a
circuit for reading a current flowing in a selected memory cell, a
voltage suppressor circuit for suppressing fluctuation of the second
voltage with respect to each word line and bit line provided in the
circuit for applying the second voltage, and a second voltage control
circuit for applying the first voltage to the selected bit line and a
dummy second voltage to the unselected bit lines and the word lines
during the preset period and controlling the voltage suppressor circuit
during a reading period so that the second voltage may fluctuate in a
fluctuation direction of the first voltage.