Abstract: On account of close relationship between the intake noise attenuation and the position of the noise reduction element, the intake noise of engine was analyzed using GT-Power. A Helmholtz resonator and a quarter wave tube were designed to reduce the intake noise of engine. In order to establish the relationships between the order noise and the position of Helmholtz resonator or quarter wave tube, the acoustic mode of the intake system were analyzed in SYSNOISE. The simulation results showed that 5 dB order noise reduction was obtained at the acoustic modal frequency when Helmholtz resonator or quarter wave tube was located at the antinodes of the acoustic mode comparing to that at the nodes.