Abstract: Designs and develops a passenger vehicle muffler using GT-Power. In foundation of the correlation theories about the muffler, the simulation model for analysis insertion loss and pressure loss of the muffler is established by coupling the engine working processes and muffler based on GT-Power. Designs the passenger vehicle muffler whose insertion loss achieved 31.5dB(A) under the design requirements of pressure loss no more than 22kPa,which satisfied silencers noise elimination performance index. Finally,the simulation results and the test results of this model tally well.