To provide an exhaust gas treatment apparatus capable of extending the life of a carbonaceous adsorbent such as activated carbon or the like and capable of suitably removing a harmful substance, and a control method therefor.

A control unit 5 controls a flow rate adjusting valve 14 on the basis of the future quantity of exhaust gas and the future concentration of a substance to be treated obtained through a communication line L10 to adjust the amount of the carbonaceous adsorbent taken out of an adsorbing device 1 so that the concentration of the substance to be treated at an outlet satisfies a target value over the future and the stagnation time of the carbonaceous adsorbent is taken long.