A non-volatile semiconductor memory device raises the word line voltage by use of the edge of a clock to read out memory cell data. A plurality of voltage raising circuits are connected in parallel and each of the voltage raising circuits raises a power supply voltage. A level shifter is connected to the outputs of the plurality of voltage raising circuits to drive the word line. Driving means drives each of the plurality of voltage raising circuits by use of clocks each having only one edge in a period from the address changing time to the memory cell data readout starting time at which the precharging operation is terminated. The clocks for driving the voltage raising circuits have a phase difference with respect to one another for the respective voltage raising circuits.