The utility model provides a wide band sound -attenuating structure for engine air intake system, include: the intake pipe, the section of thick bamboo wall that has the cylinder, section of thick bamboo wall has and link up a plurality of apertures of section of thick bamboo wall, with the cover body, follow the length direction of intake pipe extends the predetermined distance, and follow the circumferencial direction of section of thick bamboo wall is in cover on the partial circumference of section of thick bamboo wall section of thick bamboo wall, thereby by a section of thick bamboo wall with a cavity has been injectd to the cover body, wherein, a plurality of little pore size distributions are in a section of thick bamboo wall partial circumference on and with the cavity intercommunication. The utility model discloses a wide band sound -attenuating structure for engine air intake system sets up wide band sound -attenuating structure on the partial circumference through the radial direction of intake pipe at air intake system, under the prerequisite of avoiding dust and rainwater to invade, can arrange that reliability and durability are better relatively in a flexible way in irregular space, and the risk that acoustics was revealed is low, and the cost is relatively low.