A method of programming a non-volatile memory device includes applying a power supply voltage to a drain select line, applying a high level voltage to a drain-side pass word line or a source-side pass word line, and applying a pass voltage to unselected word lines and a program voltage to a selected word line. The high level voltage is applied to the drain-side pass word line or the source-side pass word line before applying the pass voltage to the unselected word lines and the program voltage to the selected word line.