Through analyzing the harm of the exhaust noise from the excavator, this paper illuminated the importance of the noise measurement and analysis work,. According to some correlative measurement standards, using some instruments in hand, a set of exhaust noise measurement system especially for the excavator was designed. The exhaust engine noise from an excavator produced by a construction machinery corporation was measured and analyzed, and then, seven mufflers with different structures were designed. After analyzing the frequency spectrums of seven impedance mufflers of different structures respectively, we selected the muffler j which was of best noise elimination performance among the seven mufflers. The highest noise elimination of muffler j was up to 16.3dB, which could reduce the exhaust noise from the excavator in a larger degree. At last, we analyzed the structures and corresponding effects of noise elimination for the seven mufflers and made some important conclusions.