A touch sensing system for detecting at least one touch is provided. The touch sensing system includes a touch sensing unit having a plurality of touchable regions for outputting sensing signals of the at least one touch, an operating unit for determining difference values between the sensing signals and a baseline value, a group setting unit for grouping ones of the regions in which the difference values exist into one or more groups, and a threshold value determining unit for determining maximum difference values from the groups to determine first threshold values of the groups corresponding to the determined maximum difference values. The touch sensing system increases the correctness of the touch detection by adaptively changing the first threshold value in accordance with the touch strength. A method of driving the touch sensing system is also provided.