Combustion gas extraction probe and method for operating the same

To provide a combustion gas extraction probe capable of sufficiently cooling extraction gas even when an extraction rate is increased, and capable of performing operation for maintaining predetermined chlorine removal efficiency, and a method for operating the same. A probe 2 comprises: an inner pipe 21 that extracts part of combustion gas G1 from a kiln 1; and a plurality of discharge ports 25 that are bored in the inner pipe 21, and each discharge cold air C in a direction perpendicular to a flow direction of extraction gas G2 extracted by the inner pipe 21 and in a center direction of the flow of the extraction gas G2. The discharge ports 25 discharge the cold air C so that a ratio (MC/MG) of a momentum MC of the cold air C per mouth of the discharge port 25 to a momentum MG of the extraction gas G2 satisfies 1.2 to 4.0, and a value (m-1) obtained by dividing a ratio (VC/VG) of a wind speed VC of the cold air C to a wind speed VG of the extraction gas G2 by an inner diameter D of the inner pipe 21 satisfie