A touch sensing system and a method for driving the same. The touch sensing system includes a pen with a resonant circuit embedded therein, XY electrodes including X electrodes and Y electrodes substantially perpendicular to the X electrodes, an antenna surrounding the XY electrodes, and a first touch driving circuit. The first touch driving circuit supplies a resonant inductive signal to the XY electrodes, analyzes a resonance signal received through the antenna, and decides a location and a pen pressure of the pen. The resonant inductive signal includes N periods each having a different duration, and wherein N is a positive integer equal to or greater than 2.