A semiconductor memory device is operated by, inter alia: precharging a bit line, providing a first voltage to a coupling circuit for coupling the bit lines and cell strings of a plurality of memory cells, providing a program voltage to a selected word line coupled to a memory cell on which a program operation will be performed among the plurality of memory cells, providing a pass voltage to unselected word lines, providing a second voltage lower than the first voltage to the coupling circuit, discharging the bit line by loading program data, and providing a third voltage lower than the second voltage to the coupling circuit.