A filter tuning system for quickly compensating a time constant using a binary search algorithm is disclosed. The filter tuning system includes a time constant detector, a comparator and a calibration unit. The time constant detector detects a time constant of a filter based on an integral value of a reference input signal using an integrator when the time constant of the filter changes according to a variation of a manufacturing process or a temperature. The integrator includes a capacitor changing according to a variation of the time constant of the filter. The comparator compares the detected time constant with a reference value. The calibration unit compensates the time constant of the filter using the binary search algorithm based on the comparison result until an error between the time constant and the reference value is reduced within an acceptable range.