PROBLEM TO BE SOLVED: To provide a method with which the measurement of component gas concentration in the atmosphere in a heating furnace can accurately be performed by utilizing the existing facility. SOLUTION: In the heating furnace having the storage type burners disposed as facing the burner pair attached to the heat-storing body as the heating source, each pair of the burners in the heat-storage type burners are alternately burnt, and exhaust gas in the furnace is sucked from the burner at non-burning and the heat in the exhaust gas is recovered into the heat-storing body by introducing the exhaust gas into the heat-storing body. When the operation of the heating furnace is performed by utilizing the recovered heat to the heating of the air for combustion in the burner at the combustion, a part of the exhaust gas sucked from the above burner is introduced to an analyzer to measure the component concentration in the exhaust gas.