A semiconductor memory device comprises a column readout voltage supply
circuit which supplies a predetermined first voltage when readout is
selected and supplies a predetermined second voltage which is different
from the fist voltage when the readout is not selected, to each column
selection line, a row readout voltage supply circuit which supplies the
second voltage to each row selection line at the time of readout, a sense
circuit which detects a current flowing in the selected row selection
line separately from a current flowing in the non-selected row selection
lines to detect an electric resistance state of the selected memory cell
at the time of readout, and a column voltage displacement prevention
circuit which prevents displacement of a supplied voltage level for each
of the non-selected column selection lines at the time of readout.