In this paper, principium of exhaust system standing wave was analyzed from theory and simulation calculate . The exhaust system tailpipe noise acoustic model was built with GT-power. Seen from acoustic characters of the exhaust system tailpipe noise, a long tailpipe stand wave is the root cause for peak of the common frequency. Therefore, two proposals was adopted. One proposal is to change the tailpipe length, keep away from the frequency, decrease the stand wave effect; another proposal is to design a resonator for solve this common frequency, eliminate this frequency noise; The simulation of the two proposals proved to improve the acoustic performance and achieve the target.