To provide an exhaust gas purifying system for an internal combustion engine capable of executing an optimal regenerative operation by predicting a temperature of an absorbent based on running state information.There are predicted the amount of nitrogen oxides (NO.sub.x) to be absorbed by an absorbent 125 incorporated in a catalyst 124 and the temperature of the absorbent, based on the running state information obtained from a car navigation system 141 or traffic information service receiver 142, and the regenerative operation schedule is determined based on the prediction. Thus, the regenerative operation is conducted at the timing where NO.sub.x has been duly absorbed by the absorbent and the absorbent temperature is lower than a predetermined temperature, so that the leakage of NO.sub.x into the exterior of a vehicle can be restrained.