The utility model relates to an impedance muffler which comprises a outline border; wherein, a plurality of impedance anechoic pieces are arranged on the outline border, the impedance anechoic piece comprises a keel, a clapboard arranged on the middle of the keel, a resistive anechoic unit and a reactive anechoic unit are arranged at the keel of the two sides of the clapboard, the resistive anechoic unit and the reactive anechoic unit are arranged on the left and right side of the clapboard or on the top and bottom of the clapboard. The utility model has the advantage of wide anechoic bandwidth and good high frequency muffling the same as resistive anechoic device, as well as good low and medium frequency muffling the same as reactive anechoic device, decreasing the quantity of anechoic pipes efficiently, simple structure, reducing gas-flow resistance and low cost. The utility model is widely used in noise elimination of the large gas-fuel boiler funnel.