A method for driving a display panel is disclosed to form a desired waveform in driving a pulse width modulation (PWM) mode for adjusting a gray scale level. The method for driving a display panel includes the steps of turning off a plurality of signals respectively applied from a data line and/or a scan line based on a falling edge of one scan pulse, and transiting the signals to a turn-on state to have a predetermined pulse width, thereby adjusting a gray level of the signals using a pulse width modulation mode.