Provided is a method of programming a non-volatile memory device. The method includes applying a first programming pulse to a corresponding wordline of the non-volatile memory device, applying a second programming pulse to the wordline, wherein a voltage of the second programming pulse is different from that of the first programming pulse, and applying voltages to each bitline connected to the wordline, the voltages applied to each of the bitlines are different from each other according to a plurality of bit values to be programmed to corresponding memory cells in response to the first programming pulse or the second programming pulse.